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Acoustics simulation for stadium design using EASE: analyzing acoustics and providing retrofit options for the Los Angeles Memorial Coliseum
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Acoustics simulation for stadium design using EASE: analyzing acoustics and providing retrofit options for the Los Angeles Memorial Coliseum
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Content
ACOUSTICS SIMULATION FOR STADIUM DESIGN USING EASE
Analyzing acoustics and providing retrofit options for the Los Angeles Memorial Coliseum
By
Santhosh Kumar Seeralaselvan
Presented to the
FACULTY OF THE
SCHOOL OF ARCHITECTURE
UNIVERSITY OF SOUTHERN CALIFORNIA
In partial fulfillment of the
Requirements of degree
MASTER OF BUILDING SCIENCE
MAY 2019
2
Thesis committee
CHAIR:
Karen Kensek, LEED AP BD+C
Associate Professor of the Practice of Architecture
USC School of Architecture
kensek@usc.edu
(213)740-2081
COMMITTEE MEMBER #2
Douglas Noble, FAIA, Ph.D.
Associate Professor
USC School of Architecture
dnoble@usc.edu
213 740-2723
COMMITTEE MEMBER #3
Joon Ho Choi, Ph.D., LEED AP
Assistant Professor of Building Science
USC School of Architecture
joonhoch@usc.edu
ADVISOR:
Neil Shaw, FASA
Menlo Scientific Acoustics, Inc.
Topanga, California.
www.menlozone.com
shaw.n@menlozone.com
3
Acknowledgements
I would be failing in my duty if I am not thanking the people who have helped me behind the scenes to
complete my thesis.
Firstly, I would like to thank my thesis committee chair Prof. Karen Kensek whom I fondly call as my USC
mother. She has been immensely supportive during the two years of my Building Science program at USC. Her
guidance in research methods and writing helped me produce a quality work. Her commitment and dedication to
work will always serve as an inspiration to me all my life.
Next, I would like to thank Prof. Douglas Noble, director of the Building Science program and my second
committee member. I will always be grateful to him for providing the right motivation at the hour of need.
I would also like to thank Prof. Joon-Ho Choi, my third committee member who has been supportive
during my building science program.
I would like to thank Prof. Marc Schiler and Prof. Kyle Konis for providing valuable inputs in the thesis
studio classes which helped me finetune my final product.
I am indebted to Mr. Neil Shaw from Menlo Acoustics, Topanga for helping me conduct the field study at
Harris Hall courtyard with his equipment and for all the acoustic knowledge and support by serving as an advisor to
my thesis.
I would also like to thank Dr. Elizabeth Valmont & Dr. Matt Wilkinson from ARUP for their acoustic
input, data on the Coliseum which was helpful in developing the EASE simulation model.
I would like to thank Prof. Michael Hricak and Michael Dombrowa for their continued support through my
two years of graduate program at USC school of Architecture.
I would like to thank Enrique from USC school of Architecture for providing speaker and amplifier
equipment for the field study at Harris Hall courtyard.
I would like to thank Facility Management Services at University of Southern California and Coliseum
commission for providing drawings of the Coliseum which were helpful in developing the simulation models.
I am indebted to Afmg for providing license to use the EASE software program for my thesis research and
support all my requests.
I would also like to thank Bengt-Inge Dalenbäck from CATT Acoustic for his inputs on acoustic
simulations which helped me get a clarity on my research.
4
I would like to thank my MBS peers for the amazing two years together with so many memories which I
will cherish forever.
Special thanks to my amazing MBS juniors Aniizhai Thirumeni and Nikhita Sapuram for their help and
support during my thesis.
I am incredibly thankful to my two friends Achyuthan and Poornima for being my pacifiers during times
when things didn’t go my way and giving the pep talk whenever I needed one.
Finally, I am thankful to my family for their unconditional support in my life long pursuit of excellence.
5
Abstract
A tool was developed to study the acoustics of a football stadium so that design retrofit decisions could be
quickly studied. First, a courtyard space was chosen as a test case. A Revit 3d model of the space was created, and a
field study was performed to gather sound decibel measurements. A Dynamo script was developed to extract the
geometry, material properties, location of sound sources, data collection points, and then perform a ray trace
analysis. After the development of the Dynamo script for running the acoustic simulation on Revit models, the script
crashed due to the instability of the software that could not handle the complex calculations associated with the ray
tracing algorithm. Even after trying several methods of simplifying the script to perform the same set of calculations,
the script crashed. It was concluded that the current version of Dynamo cannot handle the complexity of the script.
In order to proceed, the acoustical software EASE was chosen. It was first tested by comparing real data
from measurements in Harris Hall courtyard to the simulation. The acoustic simulation of the courtyard provided
slightly higher sound levels results than the acoustic field study data, which is probably due to the presence of trees
in the courtyard that could not be included in the EASE model.
In a second case study, acoustical data was gathered at the Los Angeles Memorial Coliseum during several
football games, and a simplified digital model of the stadium was created in AutoCAD and exported to Sketchup.
Acoustic conditions of the existing stadium were simulated in EASE. The results were compared to verify that the
simulation was reasonable in line with the real data. Then two design options were proposed. The first option was
the same being made for the ongoing Coliseum renovation. The second option has a partial roof system over the
north and south stands. The results from the acoustic simulation showed that the presence of a canopy over the
audience seating in the Coliseum provided reverberation with the sound directed towards the pitch that will create an
intense atmosphere during the football games. The sound levels were spread evenly throughout the audience stands
after reconfiguring the audio systems increased peak values up to 113 dB. The overall efficiency of the speaker
system in the stadium also improved with the addition of the partial roof system.
6
Hypothesis
Providing a partial roof over the audience stands in the Los Angeles Memorial Coliseum will increase the
sound pressure levels (SPL) in the stadium and can provide an intimidating experience for the away team.
Research Objectives
1. To develop a visual programming script to simulate acoustics in Dynamo for Revit
2. To conduct an acoustic field study of the Harris Hall courtyard that will be used as a case study for the acoustic
simulation.
3. To conduct acoustic field study at the Los Angeles Memorial Coliseum during the college football season to
collect data and use it as a case study for the simulation
4. To validate the results using acoustic software EASE and Pachyderm.
5. After validation, to make design changes to the existing model and simulate, analyze, and provide a better acoustic
solution for the Los Angeles Memorial Coliseum.
7
Table of Contents
Thesis committee ........................................................................................................................................................... 2
Acknowledgements ....................................................................................................................................................... 3
Abstract.......................................................................................................................................................................... 5
Hypothesis ..................................................................................................................................................................... 6
Research Objectives ...................................................................................................................................................... 6
Table of Contents........................................................................................................................................................... 7
Table of Figures ........................................................................................................................................................... 13
Table of Tables ............................................................................................................................................................ 25
Chapter 1: Introduction ................................................................................................................................................ 33
1.1 Overview ....................................................................................................................................... 33
1.2 Computer aided design, building information modelling, and visual programming ..................... 33
1.2.1 Computer aided design .................................................................................................................. 33
1.2.2 Building information modeling ..................................................................................................... 33
1.2.3 Visual programming ...................................................................................................................... 34
1.3 Architectural Acoustics ................................................................................................................. 40
1.3.1 Geometric Acoustics ..................................................................................................................... 41
1.3.2 Sound reflection ............................................................................................................................ 41
1.3.3 Sound diffraction ........................................................................................................................... 42
1.3.4 Sound absorption, absorption coefficient ...................................................................................... 42
1.3.5 Sound diffusion ............................................................................................................................. 43
1.3.6 Sound growth and decay, reverberation time ................................................................................ 43
1.3.7 Acoustic parameters which define the acoustic quality of a space ................................................ 44
1.4 Stadium acoustics .......................................................................................................................... 46
1.4.1 Shape, seating and roof configuration ........................................................................................... 46
8
1.4.2 Sound and distance ........................................................................................................................ 46
1.5 Acoustic simulation software ........................................................................................................ 46
1.5.1 EASE- Enhanced Acoustic Simulator for Engineers .................................................................... 47
1.5.2 Odeon ............................................................................................................................................ 48
1.5.3 CATT-Acoustics ........................................................................................................................... 49
1.5.4 Pachyderm ..................................................................................................................................... 49
1.5.5 REW- Room EQ Wizard ............................................................................................................... 50
1.5.6 SoundPLAN Essentials ................................................................................................................. 51
1.6 Acoustic measurement equipment and software ........................................................................... 52
1.6.1 Acoustic measurement equipment ................................................................................................. 52
1.6.2 Acoustic measurement software .................................................................................................... 53
1.7 Glossary of terms and abbreviations ............................................................................................. 55
1.7.1 Glossary of terms .......................................................................................................................... 55
1.7.2 Abbreviations ................................................................................................................................ 56
1.8 Summary ....................................................................................................................................... 56
Chapter 2: Literature Review ....................................................................................................................................... 57
2.1 Overview ....................................................................................................................................... 57
2.2 Building information modeling, visual programing ...................................................................... 57
2.2.1 Building information modelling .................................................................................................... 57
2.2.2 Visual programming ...................................................................................................................... 57
2.3 Architectural acoustics .................................................................................................................. 58
2.4 Stadium acoustics .......................................................................................................................... 59
2.4.1 Noise emanating from the stadium ................................................................................................ 59
2.4.2 Stadium simulation ........................................................................................................................ 60
2.4.3 Noise generated by fans ................................................................................................................ 61
9
2.5 Acoustic simulation ....................................................................................................................... 63
2.5.1 EASE features ............................................................................................................................... 63
2.5.2 Errors in EASE .............................................................................................................................. 63
2.5.3 Reverberation time, (Boeck, Navvab, & Heilmann, 2012) ........................................................... 64
2.6 Summary ....................................................................................................................................... 65
Chapter 3: Methodology .............................................................................................................................................. 66
3.1 Overview and demo model study .................................................................................................. 66
3.2 Harris Hall courtyard at University of Southern California .......................................................... 70
3.2.1 Real time acoustic study at the Harris Hall courtyard at University of Southern California ......... 71
3.2.2 Revit & Dynamo ........................................................................................................................... 75
3.2.3 Acoustic software simulation – EASE .......................................................................................... 78
3.3 Los Angeles Memorial Coliseum .................................................................................................. 82
3.3.1 Real time acoustic analysis of the Los Angeles Memorial Coliseum during the 2017-18 college
football season ............................................................................................................................... 83
3.3.2 Revit & Dynamo ........................................................................................................................... 85
3.3.3 Acoustic software simulation – EASE .......................................................................................... 85
3.4 Summary ....................................................................................................................................... 90
Chapter 4: Results ........................................................................................................................................................ 91
4.1 Overview and the updated methodology ....................................................................................... 91
4.2 Harris Hall courtyard at the University of Southern California..................................................... 92
4.2.1 Real time acoustic study results of Harris Hall courtyard at the University of Southern California
92
4.2.2 Revit and Dynamo ....................................................................................................................... 130
4.2.3 Acoustic software simulation- EASE .......................................................................................... 130
4.3 Los Angeles Memorial Coliseum ................................................................................................ 150
10
4.3.1 Real time acoustic study at the Los Angeles Memorial Coliseum during the 2017-18 football
season .......................................................................................................................................... 150
4.3.2 Revit & Dynamo ......................................................................................................................... 165
4.3.3 Acoustic software simulation - EASE ......................................................................................... 166
4.4 Summary ..................................................................................................................................... 182
Chapter 5: Discussion ................................................................................................................................................ 183
5.1 Overview ..................................................................................................................................... 183
5.2 Harris Hall courtyard at the University of Southern California................................................... 184
5.2.1 Observations from acoustic study results of Harris Hall courtyard at the University of Southern
California .................................................................................................................................... 184
5.2.2 Harris Hall courtyard setup-1 ...................................................................................................... 187
5.2.3 Harris Hall courtyard setup-2 ...................................................................................................... 189
5.2.4 Revit and Dynamo ....................................................................................................................... 191
5.2.5 Conclusions from Harris Hall Courtyard .................................................................................... 192
5.3 Los Angeles Memorial Coliseum ................................................................................................ 193
5.3.1 Observations from the Field study .............................................................................................. 196
5.3.2 Acoustic software simulation - EASE ......................................................................................... 211
5.3.3 Takeaways for developing the retrofit for Coliseum ................................................................... 226
5.4 Summary ..................................................................................................................................... 226
Chapter 6: Los Angeles Memorial Coliseum design modification ............................................................................ 229
6.1 Overview ..................................................................................................................................... 229
6.2 Design modification-1 ................................................................................................................. 229
6.2.1 EASE simulation analysis ........................................................................................................... 230
6.2.2 EASE simulation results .............................................................................................................. 234
6.3 Design modification-2 ................................................................................................................. 248
11
6.3.1 EASE simulation analysis ........................................................................................................... 249
6.3.2 EASE simulation results .............................................................................................................. 252
6.4 Discussion ................................................................................................................................... 280
6.4.1 Total SPL .................................................................................................................................... 280
6.4.2 C7 ................................................................................................................................................ 292
6.4.3 C50 .............................................................................................................................................. 298
6.4.4 C80 .............................................................................................................................................. 304
6.4.5 First Arrival ................................................................................................................................. 310
6.4.6 Articulation loss of consonants ................................................................................................... 311
6.4.7 Speech Transmission Index ......................................................................................................... 313
6.4.8 EASE features ............................................................................................................................. 314
6.4.9 Takeaways from the design modification analysis of the Los Angeles Memorial Coliseum using
EASE ........................................................................................................................................... 314
6.5 Summary ..................................................................................................................................... 317
Chapter 7: Conclusion & Future Work ...................................................................................................................... 322
7.1 Overview ..................................................................................................................................... 322
7.2 Acoustic simulation and field study process used for the study .................................................. 322
7.2.1 Dynamo ....................................................................................................................................... 322
7.2.2 EASE ........................................................................................................................................... 325
7.3 Case study spaces for simulating acoustics ................................................................................. 326
7.3.1 Harris Hall courtyard at University of Southern California ........................................................ 326
7.3.2 Los Angeles Memorial Coliseum ................................................................................................ 327
7.4 Takeaways from Harris Hall courtyard and Los Angeles Memorial Coliseum field study and
EASE simulation ......................................................................................................................... 329
7.5 Design modification analysis study of the Los Angeles Memorial Coliseum ............................. 331
7.6 Takeaways from the design modification analysis of the Los Angeles Memorial Colseum ....... 334
12
7.7 Future work ................................................................................................................................. 336
7.7.1 Acoustic simulation software ...................................................................................................... 336
7.7.2 Lighting retrofit at the Coliseum ................................................................................................. 337
7.7.3 Dynamo script for Harris Hall courtyard acoustic simulation ..................................................... 338
7.7.4 Pachyderm ................................................................................................................................... 338
7.7.5 Field study shortcomings and how to overcome them ................................................................ 338
7.8 Conclusion .................................................................................................................................. 339
References ................................................................................................................................................................. 342
Appendices ................................................................................................................................................................ 346
Appendix A: Acoustic measurement equipment data sheet .................................................................... 346
A.1 Bruel and Kjaer type 2250 ................................................................................................................ 346
A.2 Rolland octa capture ......................................................................................................................... 348
A.3 Audix TM-1 ...................................................................................................................................... 349
A.4 Yamaha stagepas 400i ....................................................................................................................... 351
A.5 Extech HD600 ................................................................................................................................... 355
Appendix B: Supporting data from EASERA and the field study at Harris Hall courtyard, University of
Southern California ..................................................................................................................... 356
B.1 Harris Hall courtyard field study photos ........................................................................................... 356
B.2 Revit model ....................................................................................................................................... 357
Appendix C: Supporting data from the field study conducted during the football season at the Los
Angeles Memorial Coliseum ....................................................................................................... 358
C.1 Photos from Coliseum ....................................................................................................................... 358
C.2 Excel spreadsheets from Sound Analyzer app .................................................................................. 359
Appendix D: Additional data from EASE simulation of Los Angeles Memorial Coliseum ................... 360
D.1 Sketchup model ................................................................................................................................. 360
13
D.2 EASE model ..................................................................................................................................... 360
Appendix E: Additional data from EASE simulation of Los Angeles Memorial Coliseum redesign-1 . 361
E.1 Sketchup model ................................................................................................................................. 361
E.2 EASE model ...................................................................................................................................... 361
Appendix F: Additional data from EASE simulation of Los Angeles Memorial Coliseum redesign-2 .. 362
F.1 Sketchup model ................................................................................................................................. 362
F.2 EASE model ...................................................................................................................................... 362
Appendix G: Dynamo script for Harris Hall courtyard at University of Southern California acoustic
simulation (incomplete) ............................................................................................................... 363
G.1 Revit model ....................................................................................................................................... 363
G.2 Dynamo script ................................................................................................................................... 364
Table of Figures
Figure 1.2-1 Pachyderm script in Grasshopper to simulate acoustics for a room (McNeel Associates, 2018) . ......... 35
Figure 1.2-2 Revit model of a single-family residence ................................................................................................ 36
Figure 1.2-3 Anatomy of a node (Autodesk, 2018) ..................................................................................................... 37
Figure 1.2-4 Wiring of nodes in Dynamo (Kensek, 2017) .......................................................................................... 37
Figure 1.2-5 Dynamo script creating a grid of circles (Kensek, 2017) ........................................................................ 38
Figure 1.2-6 Dynamo script showing the nodal network to create a grid of circles (Kensek, 2017) ........................... 38
Figure 1.2-7 Generative Components Interface (Bentley, 2017) ................................................................................. 40
Figure 1.2-8 Marionette visual scripting interface (Frausto-Robledo, 2015) .............................................................. 40
Figure 1.3-1 Behavior of sound in an enclosed space (Doelle, 1964) ......................................................................... 42
Figure 1.3-2 Percentile values of Ln (Castle Group Ltd, 2018)................................................................................... 44
Figure 1.5-1 Editing model in EASE ........................................................................................................................... 48
Figure 1.5-2 Odeon simulation of the Boston symphony hall (Odeon A/S, 2017) ...................................................... 48
14
Figure 1.5-3 Acoustic simulation of an auditorium using CATT-Acoustic (CATT-Acoustic, 2017) ......................... 49
Figure 1.5-4 Pachyderm script in Grasshopper (McNeel Associates, 2018) ............................................................... 50
Figure 1.5-5 Interface of REW (Room EQ Wizard, 2017) .......................................................................................... 51
Figure 1.5-6 Acoustic contour mapping in Soundplan essentials for a power plant facility (Soundplan essentials,
2017) ............................................................................................................................................................................ 51
Figure 1.6-1 EASERA collecting live acoustic data using the laptop microphone ..................................................... 53
Figure 1.6-2 Screenshot of live data collection using Sound Analyzer app ................................................................ 54
Figure 1.6-3 Google Pixel mobile device (Amazon, 2018) ......................................................................................... 54
Figure 3.1-1 An overview of the entire methodology .................................................................................................. 66
Figure 3.1-2 A Dynamo script to calculate the reverberation time of a room ............................................................. 67
Figure 3.1-3 Calculating the volume of the room ........................................................................................................ 68
Figure 3.1-4 Calculating the overall absorption of the room ....................................................................................... 69
Figure 3.1-5 Calculating the reverberation time .......................................................................................................... 69
Figure 3.2-1 Acoustic analysis of the Harris Hall courtyard at University of Southern California methodology
overview ...................................................................................................................................................................... 70
Figure 3.2-2 Harris Hall courtyard at University of Southern California .................................................................... 70
Figure 3.2-3 Acoustic analysis of the Harris Hall courtyard at University of Southern California methodology ....... 71
Figure 3.2-4 Harris Hall courtyard acoustic field study photographs .......................................................................... 72
Figure 3.2-5 Harris Hall acoustic study setup-1 .......................................................................................................... 73
Figure 3.2-6 Harris Hall acoustic study setup-2 .......................................................................................................... 74
Figure 3.2-7 Acoustic analysis of the Harris Hall courtyard at University of Southern California methodology ....... 75
Figure 3.2-8 Harris Hall courtyard Dynamo script methodology ............................................................................... 75
Figure 3.2-9 Dynamo Script showing projection of cone from the point source locations during direct sound
projection sequence ..................................................................................................................................................... 77
Figure 3.2-10 Acoustic analysis of the Harris Hall courtyard at University of Southern California methodology ..... 78
Figure 3.2-11 Harris Hall Courtyard Sketchup model images ..................................................................................... 79
Figure 3.2-12 Harris Hall courtyard EASE model ....................................................................................................... 81
Figure 3.3-1 Acoustic field study at the Los Angeles Memorial Coliseum methodology ........................................... 82
15
Figure 3.3-2 Los Angeles Memorial Coliseum during the college football game ....................................................... 82
Figure 3.3-3 Acoustic field study at the Los Angeles Memorial Coliseum methodology ........................................... 83
Figure 3.3-4 Seating chart of the Los Angeles memorial coliseum (Los Angeles Memorial Coliseum, 2017) ........... 84
Figure 3.3-5 Acoustic field study at the Los Angeles Memorial Coliseum methodology ........................................... 85
Figure 3.3-6 Acoustic field study at the Los Angeles Memorial Coliseum methodology ........................................... 85
Figure 3.3-7 Los Angeles Memorial Coliseum AutoCAD 3d model .......................................................................... 86
Figure 3.3-8 Los Angeles Memorial Coliseum Sketchup model ................................................................................. 87
Figure 3.3-9 Los Angeles Memorial Coliseum EASE model ...................................................................................... 89
Figure 4.1-1 Updated methodology diagram focusing on the acoustic analysis of the study spaces ........................... 91
Figure 4.2-1 Harris Hall courtyard methodology overview ......................................................................................... 92
Figure 4.2-2 Harris Hall courtyard acoustic field study results overview ................................................................... 93
Figure 4.2-3 Harris Hall courtyard setup-1 Log sweep Impulse response ................................................................... 95
Figure 4.2-4 Harris Hall courtyard setup-1 Log sweep Echogram (Full IR) ............................................................... 96
Figure 4.2-5 Harris Hall courtyard setup-1 Log sweep 3D waterfall graph ................................................................ 96
Figure 4.2-6 Harris Hall courtyard setup-1 Log sweep C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green –
C80, Grey – C split) ........................................................................................................................................................ 98
Figure 4.2-7 Harris Hall courtyard setup-1 MLS Impulse response .......................................................................... 100
Figure 4.2-8 Harris Hall courtyard setup-1 MLS Echogram (Full IR) ...................................................................... 101
Figure 4.2-9 Harris Hall courtyard setup-1 MLS 3D waterfall graph ........................................................................ 101
Figure 4.2-10 Harris Hall courtyard setup-1 MLS C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80,
Grey – C split) ............................................................................................................................................................... 102
Figure 4.2-11 Harris Hall courtyard setup-1 Pink noise Impulse response ............................................................... 105
Figure 4.2-12 Harris Hall courtyard setup-1 Pink noise Echogram (Full IR) ............................................................ 105
Figure 4.2-13 Harris Hall courtyard setup-1 Pink noise 3D waterfall graph ............................................................. 106
Figure 4.2-14 Harris Hall courtyard setup-1 Pink noise C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green –
C80, Grey – C split) ...................................................................................................................................................... 107
Figure 4.2-15 Harris Hall courtyard setup-1 Sweep noise Impulse response ............................................................ 110
Figure 4.2-16 Harris Hall courtyard setup-1 Sweep noise Echogram (Full IR)......................................................... 110
16
Figure 4.2-17 Harris Hall courtyard setup-1 Sweep noise 3D waterfall graph .......................................................... 111
Figure 4.2-18 Harris Hall courtyard setup-1 Sweep noise C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green –
C80, Grey – C split) ...................................................................................................................................................... 112
Figure 4.2-19 Harris Hall courtyard setup-2 Log sweep Impulse response ............................................................... 115
Figure 4.2-20 Harris Hall courtyard setup-2 Log sweep Echogram (Full IR) ........................................................... 115
Figure 4.2-21 Harris Hall courtyard setup-2 Log sweep 3D waterfall graph ............................................................ 116
Figure 4.2-22 Harris Hall courtyard setup-2 Log sweep C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green –
C80, Grey – C split) ...................................................................................................................................................... 117
Figure 4.2-23 Harris Hall courtyard setup-2 MLS Impulse response ........................................................................ 119
Figure 4.2-24 Harris Hall courtyard setup-2 MLS Echogram (Full IR) .................................................................... 119
Figure 4.2-25 Harris Hall courtyard setup-2 MLS 3D waterfall graph ...................................................................... 120
Figure 4.2-26 Harris Hall courtyard setup-2 MLS C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80,
Grey – C split) ............................................................................................................................................................... 121
Figure 4.2-27 Harris Hall courtyard setup-2 Pink noise Impulse response ............................................................... 123
Figure 4.2-28 Harris Hall courtyard setup-2 Pink noise Echogram (Full IR) ............................................................ 123
Figure 4.2-29 Harris Hall courtyard setup-2 Pink noise 3D waterfall graph ............................................................. 124
Figure 4.2-30 Harris Hall courtyard setup-2 Pink noise C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green –
C80, Grey – C split) ...................................................................................................................................................... 125
Figure 4.2-31 Harris Hall courtyard setup-2 Pink noise Impulse response ............................................................... 127
Figure 4.2-32 Harris Hall courtyard setup-2 Pink noise Echogram (Full IR) ............................................................ 127
Figure 4.2-33 Harris Hall courtyard setup-2 Pink noise 3D waterfall graph ............................................................. 128
Figure 4.2-34 Harris Hall courtyard setup-2 Pink noise C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green –
C80, Grey – C split) ...................................................................................................................................................... 129
Figure 4.2-35 Harris Hall courtyard methodology overview ..................................................................................... 131
Figure 4.2-36 Harris Hall courtyard EASE simulation results overview ................................................................... 131
Figure 4.2-37 Harris Hall courtyard setup-1 EASE simulation Total SPL mapping ................................................. 133
Figure 4.2-38 Harris Hall courtyard setup-1 EASE simulation Total SPL calculation ............................................. 133
Figure 4.2-39 Harris Hall courtyard setup-1 EASE simulation C7 mapping ............................................................. 135
17
Figure 4.2-40 Harris Hall courtyard setup-1 EASE simulation C7 calculation ......................................................... 135
Figure 4.2-41 Harris Hall courtyard setup-1 EASE simulation C50 mapping ........................................................... 137
Figure 4.2-42 Harris Hall courtyard setup-1 EASE simulation C50 calculation ....................................................... 137
Figure 4.2-43 Harris Hall courtyard setup-1 EASE simulation C80 calculation ....................................................... 139
Figure 4.2-44 Harris Hall courtyard setup-1 EASE simulation C80 calculation ....................................................... 139
Figure 4.2-45 Harris Hall courtyard setup-2 EASE simulation Total SPL mapping ................................................. 142
Figure 4.2-46 Harris Hall courtyard setup-2 EASE simulation Total SPL calculation ............................................. 142
Figure 4.2-47 Harris Hall courtyard setup-2 EASE simulation C7 mapping ............................................................. 144
Figure 4.2-48 Harris Hall courtyard setup-2 EASE simulation C7 calculation ......................................................... 144
Figure 4.2-49 Harris Hall courtyard setup-2 EASE simulation C50 mapping ........................................................... 146
Figure 4.2-50 Harris Hall courtyard setup-2 EASE simulation C50 calculation ....................................................... 146
Figure 4.2-51 Harris Hall courtyard setup-2 EASE simulation C80 mapping ........................................................... 148
Figure 4.2-52 Harris Hall courtyard setup-2 EASE simulation C80 calculation ....................................................... 148
Figure 4.3-1 Los Angeles Memorial Coliseum methodology overview ................................................................... 150
Figure 4.3-2 Los Angeles Memorial Coliseum field study data collection points ..................................................... 151
Figure 4.3-3 Los Angeles Memorial Coliseum field study results overview ............................................................. 151
Figure 4.3-4 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Western
Michigan .................................................................................................................................................................... 153
Figure 4.3-5 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Western Michigan ......... 153
Figure 4.3-6 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Stanford
Cardinals .................................................................................................................................................................... 155
Figure 4.3-7 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Stanford Cardinals......... 155
Figure 4.3-8 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Texas
Longhorns .................................................................................................................................................................. 157
Figure 4.3-9 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Texas Longhorns ........... 157
Figure 4.3-10 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Oregon
State Beavers ............................................................................................................................................................. 159
Figure 4.3-11 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Oregon State Beavers .. 159
18
Figure 4.3-12 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Utah Utes
................................................................................................................................................................................... 161
Figure 4.3-13 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Utah Utes .................... 161
Figure 4.3-14 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Arizona
Wildcats ..................................................................................................................................................................... 163
Figure 4.3-15 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Arizona Wildcats ......... 163
Figure 4.3-16 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs UCLA
Bruins ........................................................................................................................................................................ 165
Figure 4.3-17 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs UCLA Bruins .............. 165
Figure 4.3-18 Los Angeles Memorial Coliseum methodology overview .................................................................. 166
Figure 4.3-19 Los Angeles Memorial Coliseum EASE simulation results overview ................................................ 167
Figure 4.3-20 Los Angeles Memorial Coliseum EASE simulation scenario-1 Total SPL at 1000 Hz mapping ....... 169
Figure 4.3-21 Los Angeles Memorial Coliseum EASE simulation scenario-1 total SPL at listeners seats ............... 170
Figure 4.3-22 Los Angeles Memorial Coliseum EASE simulation scenario-2 Total SPL at 1000 Hz mapping ....... 171
Figure 4.3-23 Los Angeles Memorial Coliseum EASE simulation scenario-2 Total SPL at listeners seats ............. 172
Figure 4.3-24 Los Angeles Memorial Coliseum EASE simulation first arrival mapping ......................................... 173
Figure 4.3-25 Los Angeles Memorial Coliseum EASE simulation C7 mapping at 1000 Hz .................................... 174
Figure 4.3-26 Los Angeles Memorial Coliseum EASE simulation C7 calculation at listeners seats ........................ 175
Figure 4.3-27 Los Angeles Memorial Coliseum EASE simulation C50 mapping at 1000 Hz .................................. 176
Figure 4.3-28 Los Angeles Memorial Coliseum EASE simulation C50 calculation at listeners seats ...................... 177
Figure 4.3-29 Los Angeles Memorial Coliseum EASE simulation C80 mapping at 1000 Hz .................................. 178
Figure 4.3-30 Los Angeles Memorial Coliseum EASE simulation C80 calculation at listeners seats ...................... 179
Figure 4.3-31 Los Angeles Memorial Coliseum EASE simulation Articulation loss of consonants mapping .......... 180
Figure 4.3-32 Los Angeles Memorial Coliseum EASE simulation speech transmission index (STI) mapping ........ 181
Figure 5.1-1 Overall methodology overview ............................................................................................................. 183
Figure 5.2-1 Harris Hall courtyard acoustic field study methodology overview ....................................................... 184
Figure 5.2-2 Harris Hall courtyard acoustic field study results overview ................................................................. 185
Figure 5.2-3 Harris Hall courtyard EASE simulation results overview ..................................................................... 185
19
Figure 5.3-1 Los Angeles Memorial Coliseum methodology overview .................................................................... 193
Figure 5.3-2 Los Angeles Memorial Coliseum field study data collection points ..................................................... 194
Figure 5.3-3 Los Angeles Memorial Coliseum field study results overview ............................................................. 194
Figure 5.3-4 Los Angeles Memorial Coliseum EASE simulation results overview .................................................. 195
Figure 5.3-5 Los Angeles Memorial Coliseum EASE simulation audience seat locations ....................................... 196
Figure 5.3-6 Los Angeles Memorial Coliseum field study observations ................................................................... 197
Figure 5.3-7 Los Angeles Memorial Coliseum view from Student section-1 ........................................................... 200
Figure 5.3-8 Los Angeles Memorial Coliseum view from Student section-2 ........................................................... 201
Figure 5.3-9 Los Angeles Memorial Coliseum view from Northwest corner ........................................................... 203
Figure 5.3-10 Los Angeles Memorial Coliseum view from General public-1 .......................................................... 204
Figure 5.3-11 Los Angeles Memorial Coliseum view from the Titantron................................................................. 206
Figure 5.3-12 Los Angeles Memorial Coliseum view from General public-2 .......................................................... 207
Figure 5.3-13 Los Angeles Memorial Coliseum view from the away fans ............................................................... 209
Figure 5.3-14 Los Angeles Memorial Coliseum field study overall peak and minimum Total SPL at listeners seats
................................................................................................................................................................................... 210
Figure 5.3-15 Los Angeles Memorial Coliseum EASE simulation results overview ................................................ 211
Figure 5.3-16 Los Angeles Memorial Coliseum EASE simulation audience seat locations ..................................... 212
Figure 5.3-17 Los Angeles Memorial Coliseum EASE simulation scenario-1 Total SPL at 1000 Hz mapping ....... 213
Figure 5.3-18 Los Angeles Memorial Coliseum EASE simulation scenario-2 Total SPL at 1000 Hz mapping ....... 215
Figure 5.3-19 Los Angeles Memorial Coliseum EASE simulation first arrival mapping ......................................... 217
Figure 5.3-20 Los Angeles Memorial Coliseum EASE simulation C7 mapping at 1000 Hz .................................... 219
Figure 5.3-21 Los Angeles Memorial Coliseum EASE simulation C50 mapping at 1000 Hz .................................. 221
Figure 5.3-22 Los Angeles Memorial Coliseum EASE simulation C80 mapping at 1000 Hz .................................. 222
Figure 5.3-23 Los Angeles Memorial Coliseum EASE simulation Articulation loss of consonants mapping .......... 224
Figure 5.3-24 Los Angeles Memorial Coliseum EASE simulation speech transmission index (STI) mapping ........ 225
Figure 6.1-1 Los Angeles Memorial Coliseum design modification analysis overview ........................................... 229
Figure 6.2-1 Los Angeles Memorial Coliseum design modifcation-1 (proposed renovation) ................................... 230
Figure 6.2-2 Los Angeles Memorial Coliseum design modification-1 AutoCAD 3d model .................................... 231
20
Figure 6.2-3 Los Angeles Memorial Coliseum design modification-1 Sketchup model ........................................... 232
Figure 6.2-4 Los Angeles Memorial Coliseum design modification-1 EASE model ................................................ 233
Figure 6.2-5 Los Angeles Memorial Coliseum design modification-1 EASE simulation results overview .............. 234
Figure 6.2-6 Los Angeles Memorial Coliseum design modification-1 scenario-1 EASE simulation total SPL
mapping at 1000 Hz ................................................................................................................................................... 235
Figure 6.2-7 Los Angeles Memorial Coliseum design modification-1 EASE simulation scenario-1 total SPL
calculation at listeners seats ....................................................................................................................................... 236
Figure 6.2-8 Los Angeles Memorial Coliseum design modification-1 scenario-2 EASE simulation total SPL
mapping at 1000 Hz ................................................................................................................................................... 237
Figure 6.2-9 Los Angeles Memorial Coliseum design modification-1 EASE simulation scenario-2 total SPL
calculation at listeners seats ....................................................................................................................................... 238
Figure 6.2-10 Los Angeles Memorial Coliseum design modification-1 EASE simulation first arrival mapping ..... 239
Figure 6.2-11 Los Angeles Memorial Coliseum design modification-1 EASE simulation C7 mapping at 1000 Hz 240
Figure 6.2-12 Los Angeles Memorial Coliseum design modification-1 EASE simulation C7 calculation at listeners
seats ........................................................................................................................................................................... 241
Figure 6.2-13 Los Angeles Memorial Coliseum design modification-1 EASE simulation C50 mapping at 1000 Hz
................................................................................................................................................................................... 242
Figure 6.2-14 Los Angeles Memorial Coliseum design modification-1 EASE simulation C50 calculation at listeners
seats ........................................................................................................................................................................... 243
Figure 6.2-15 Los Angeles Memorial Coliseum design modification-1 EASE simulation C80 mapping at 1000 Hz
................................................................................................................................................................................... 244
Figure 6.2-16 Los Angeles Memorial Coliseum design modification-1 EASE simulation C80 calculation at listeners
seats ........................................................................................................................................................................... 245
Figure 6.2-17 Los Angeles Memorial Coliseum design modification-1 EASE simulation Articulation loss of
consonants mapping .................................................................................................................................................. 246
Figure 6.2-18 Los Angeles Memorial Coliseum design modification EASE simulation speech transmission index
(STI) mapping ........................................................................................................................................................... 247
Figure 6.3-1 Los Angeles Memorial Coliseum design modification-2 section through the Sketchup model............ 248
21
Figure 6.3-2 Los Angeles Memorial Coliseum design modification-2 view inside the Coliseum Sketchup model .. 248
Figure 6.3-3 Los Angeles Memorial Coliseum design modification-2 AutoCAD 3d model .................................... 249
Figure 6.3-4 Los Angeles Memorial Coliseum design modification-2 Sketchup model ........................................... 250
Figure 6.3-5 Los Angeles Memorial Coliseum design modification-2 EASE model ................................................ 251
Figure 6.3-6 Los Angeles Memorial Coliseum design modification-2 results overview .......................................... 252
Figure 6.3-7 Los Angeles Memorial Coliseum design modification-2 setup-1 layout .............................................. 253
Figure 6.3-8 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-1 total SPL
mapping at 1000 Hz ................................................................................................................................................... 253
Figure 6.3-9 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-1 total SPL
calculation at listeners seats ....................................................................................................................................... 254
Figure 6.3-10 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-2 total
SPL mapping at 1000 Hz ........................................................................................................................................... 255
Figure 6.3-11 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-2 total
SPL calculation at listeners seats ............................................................................................................................... 256
Figure 6.3-12 Los Angeles Memorial Coliseum design modification-2 setup-2 ....................................................... 257
Figure 6.3-13 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-1 total
SPL mapping at 1000 Hz ........................................................................................................................................... 258
Figure 6.3-14 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-1 total
SPL calculation at listeners seats ............................................................................................................................... 259
Figure 6.3-15 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-2 total
SPL mapping at 1000 Hz ........................................................................................................................................... 260
Figure 6.3-16 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-2 total
SPL calculation at listeners seats ............................................................................................................................... 261
Figure 6.3-17 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 first arrival
mapping ..................................................................................................................................................................... 262
Figure 6.3-18 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 first arrival
mapping ..................................................................................................................................................................... 263
22
Figure 6.3-19 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C7 mapping at
1000 Hz ..................................................................................................................................................................... 264
Figure 6.3-20 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C7 calculation at
listeners seats ............................................................................................................................................................. 265
Figure 6.3-21 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C7 mapping at
1000 Hz ..................................................................................................................................................................... 266
Figure 6.3-22 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C7 calculation at
listeners seats ............................................................................................................................................................. 267
Figure 6.3-23 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C50 mapping at
1000 Hz ..................................................................................................................................................................... 268
Figure 6.3-24 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C50 calculation at
listeners seats ............................................................................................................................................................. 269
Figure 6.3-25 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C50 mapping at
1000 Hz ..................................................................................................................................................................... 270
Figure 6.3-26 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C50 calculation at
listeners seats ............................................................................................................................................................. 271
Figure 6.3-27 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C80 mapping at
1000 Hz ..................................................................................................................................................................... 272
Figure 6.3-28 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C80 calculation at
listeners seats ............................................................................................................................................................. 273
Figure 6.3-29 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C80 mapping at
1000 Hz ..................................................................................................................................................................... 274
Figure 6.3-30 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C80 calculation at
listeners seats ............................................................................................................................................................. 275
Figure 6.3-31 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 Articulation loss of
consonants mapping .................................................................................................................................................. 276
Figure 6.3-32 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 Articulation loss of
consonants mapping .................................................................................................................................................. 277
23
Figure 6.3-33 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 Speech
Transmission Index mapping ..................................................................................................................................... 278
Figure 6.3-34 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 Speech
Transmission Index mapping ..................................................................................................................................... 279
Figure 6.4-1 Los Angeles Memorial Coliseum design modification analysis methodology overview ..................... 280
Figure 6.4-2 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 mapping ... 291
Figure 6.4-3 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 mapping ... 292
Figure 6.4-4 Los Angeles Memorial Coliseum EASE simulation comparison of C7 mapping ................................. 298
Figure 6.4-5 Los Angeles Memorial Coliseum EASE simulation comparison of C50 mapping ............................... 304
Figure 6.4-6 Los Angeles Memorial Coliseum EASE simulation comparison of C80 mapping ............................... 310
Figure 6.4-7 Los Angeles Memorial Coliseum EASE simulation comparison of first arrival timings ..................... 311
Figure 6.4-8 Los Angeles Memorial Coliseum EASE simulation comparison of Articulation loss of consonants ... 312
Figure 6.4-9 Los Angeles Memorial Coliseum EASE simulation comparison of speech transmission index .......... 314
Figure 7.2-1 Dynamo Script showing projection of cone from the point source locations during direct sound
projection sequence ................................................................................................................................................... 324
Figure 7.2-2 Harris Hall courtyard Dynamo script methodology ............................................................................. 325
Figure 7.2-3 Workflow from AutoCAD to EASE ..................................................................................................... 326
Figure 7.3-1 Harris Hall courtyard at University of Southern California .................................................................. 327
Figure 7.3-2 Los Angeles Memorial Coliseum during the college football game ..................................................... 328
Figure 7.6-1 Los Angeles Memorial Coliseum comparison between existing and proposed retrofit ........................ 335
Figure 7.7-1 Los Angeles Memorial Coliseum EASE simulation additional data points .......................................... 337
Figure 7.7-2 Los Angeles Memorial Coliseum lighting retrofit future study ............................................................ 338
Figure 7.7-3 Spider cam used in the stadiums ........................................................................................................... 339
Figure 7.8-1 Los Angeles Memorial Coliseum comparison between various iterations ........................................... 341
Figure A.1-1 Bruel & Kjaer type 2250 datasheet-1 (Bruel & Kjaer, 2018) ............................................................... 346
Figure A.1-2 Bruel & Kjaer type 2250 datasheet-2 (Bruel & Kjaer, 2018) ............................................................... 347
Figure B.1-1 Harris Hall courtyard field study photograph-1.................................................................................... 356
Figure B.1-2 Harris Hall courtyard field study photograph-2.................................................................................... 356
24
Figure C.1-1 Los Angeles Memorial Coliseum post-game band performance .......................................................... 358
Figure C.1-2 Los Angeles Memorial Coliseum halftime band performance ............................................................. 358
Figure D.1-1 Los Angeles Memorial Coliseum Sketchup model .............................................................................. 360
Figure E.1-1 Los Angeles Memorial Coliseum design modification-1 Sketchup model........................................... 361
Figure F.1-1 Los Angeles Memorial Coliseum design modification-2 Sketchup model images............................... 362
Figure G.1-1 Harris Hall courtyard Revit model southwest isometric view .............................................................. 363
25
Table of Tables
Table 1.5-1 Acoustic simulation software available in the market .............................................................................. 47
Table 1.6-1 Acoustic measurement equipment ............................................................................................................ 52
Table 3.2-1 Harris Hall courtyard EASE model material list ...................................................................................... 79
Table 3.3-1 USC Trojans college football 2017-18 season schedule and results (University of Southern California
Athletics, 2018) ........................................................................................................................................................... 84
Table 3.3-2 Los Angeles Memorial Coliseum EASE material list .............................................................................. 88
Table 4.2-1 Harris Hall courtyard setup-1 log sweep STI, AlCons, RaSTI ................................................................. 97
Table 4.2-2 Harris Hall courtyard setup-1 Log sweep Clarity measures ..................................................................... 98
Table 4.2-3 Harris Hall courtyard setup-1 Log sweep results ..................................................................................... 99
Table 4.2-4 Harris Hall courtyard setup-1 MLS signal STI, AlCons, RaSTI ............................................................ 102
Table 4.2-5 Harris Hall courtyard setup-1 MLS Clarity measures ............................................................................ 103
Table 4.2-6 Harris Hall courtyard setup-1 MLS results ............................................................................................. 104
Table 4.2-7 Harris Hall courtyard setup-1 Pink noise signal STI, AlCons, RaSTI.................................................... 107
Table 4.2-8 Harris Hall courtyard setup-1 Pink noise Clarity measures .................................................................... 108
Table 4.2-9 Harris Hall courtyard setup-1 Pink noise results .................................................................................... 109
Table 4.2-10 Harris Hall courtyard setup-1 Sweep noise signal STI, AlCons, RaSTI .............................................. 112
Table 4.2-11 Harris Hall courtyard setup-1 Sweep noise Clarity measures .............................................................. 113
Table 4.2-12 Harris Hall courtyard setup-1 Sweep noise results ............................................................................... 114
Table 4.2-13 Harris Hall courtyard setup-2 log sweep STI, AlCons, RaSTI ............................................................. 116
Table 4.2-14 Harris Hall courtyard setup-2 Log sweep Clarity measures ................................................................. 117
Table 4.2-15 Harris Hall courtyard setup-2 Log sweep results ................................................................................. 118
Table 4.2-16 Harris Hall courtyard setup-2 log sweep STI, AlCons, RaSTI ............................................................. 120
Table 4.2-17 Harris Hall courtyard setup-2 MLS Clarity measures .......................................................................... 121
Table 4.2-18 Harris Hall courtyard setup-2 MLS results ........................................................................................... 122
Table 4.2-19 Harris Hall courtyard setup-2 log sweep STI, AlCons, RaSTI ............................................................. 124
Table 4.2-20 Harris Hall courtyard setup-2 Pink noise Clarity measures .................................................................. 125
26
Table 4.2-21 Harris Hall courtyard setup-2 Pink noise results .................................................................................. 126
Table 4.2-22 Harris Hall courtyard setup-2 log sweep STI, AlCons, RaSTI ............................................................. 128
Table 4.2-23 Harris Hall courtyard setup-2 Pink noise Clarity measures .................................................................. 129
Table 4.2-24 Harris Hall courtyard setup-2 Pink noise results .................................................................................. 130
Table 4.2-25 Harris Hall courtyard setup-1 EASE simulation ambient noise input data........................................... 132
Table 4.2-26 Harris Hall courtyard setup-1 EASE simulation Total SPL calculation ............................................... 134
Table 4.2-27 Harris Hall courtyard setup-1 EASE simulation .................................................................................. 136
Table 4.2-28 Harris Hall courtyard setup-1 EASE simulation C50 calculation ........................................................ 138
Table 4.2-29 Harris Hall courtyard setup-1 EASE simulation C80 calculation ........................................................ 140
Table 4.2-30 Harris Hall courtyard setup-2 EASE simulation ambient noise input data........................................... 141
Table 4.2-31 Harris Hall courtyard setup-2 EASE simulation Total SPL calculation ............................................... 143
Table 4.2-32 Harris Hall courtyard setup-2 EASE simulation C7 calculation .......................................................... 145
Table 4.2-33 Harris Hall courtyard setup-2 EASE simulation C50 calculation ........................................................ 147
Table 4.2-34 Harris Hall courtyard setup-2 EASE simulation C80 calculation ........................................................ 149
Table 4.3-1 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs
Western Michigan...................................................................................................................................................... 152
Table 4.3-2 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs
Stanford Cardinals ..................................................................................................................................................... 154
Table 4.3-3 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs Texas
Longhorns .................................................................................................................................................................. 156
Table 4.3-4 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs Oregon
State Beavers ............................................................................................................................................................. 158
Table 4.3-5 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs Utah
Utes ............................................................................................................................................................................ 160
Table 4.3-6 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs
Arizona Wildcats ....................................................................................................................................................... 162
Table 4.3-7 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs UCLA
Bruins ........................................................................................................................................................................ 164
27
Table 4.3-8 Los Angeles Memorial Coliseum EASE simulation input data ............................................................. 167
Table 4.3-9 Los Angeles Memorial Coliseum EASE simulation scenario-1 total SPL at listeners seats .................. 170
Table 4.3-10 Los Angeles Memorial Coliseum EASE simulation scenario-2 total SPL at listeners seats ................ 172
Table 4.3-11 Los Angeles Memorial Coliseum EASE simulation first arrival calculation at listeners seats ............ 173
Table 4.3-12 Los Angeles Memorial Coliseum EASE simulation C7 calculation at listeners seats ......................... 175
Table 4.3-13 Los Angeles Memorial Coliseum EASE simulation C50 calculation at listeners seats ....................... 177
Table 4.3-14 Los Angeles Memorial Coliseum EASE simulation C80 calculation at listeners seats ....................... 179
Table 4.3-15 Los Angeles Memorial Coliseum EASE simulation Articulation loss of consonants calculation at
listeners seats ............................................................................................................................................................. 180
Table 4.3-16 Los Angeles Memorial Coliseum EASE simulation speech transmission index (STI) at listeners seats
................................................................................................................................................................................... 181
Table 5.2-1 Recommended values for acoustic variables (ADA (Acoustic Design Anhert), 2009) .......................... 187
Table 5.2-2 Harris Hall courtyard setup-1 field study results .................................................................................... 188
Table 5.2-3 Harris Hall courtyard setup-1 EASE simulation results ......................................................................... 189
Table 5.2-4 Harris Hall courtyard setup-2 field study results .................................................................................... 190
Table 5.2-5 Harris Hall courtyard setup-2 EASE simulation results ......................................................................... 191
Table 5.3-1 USC Trojans college football 2017-18 season schedule and results (University of Southern California
Athletics, 2018) ......................................................................................................................................................... 198
Table 5.3-2 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at student section-1 .. 199
Table 5.3-3 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at student section-1
................................................................................................................................................................................... 199
Table 5.3-4 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at student section-2 .. 201
Table 5.3-5 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at student section-2
................................................................................................................................................................................... 201
Table 5.3-6 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at northwest corner ... 202
Table 5.3-7 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at northwest corner
................................................................................................................................................................................... 203
Table 5.3-8 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at general public-1 ... 204
28
Table 5.3-9 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at general public-1
................................................................................................................................................................................... 204
Table 5.3-10 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at Titantron ............. 205
Table 5.3-11 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at Titantron ..... 205
Table 5.3-12 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at general public-2 . 207
Table 5.3-13 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at general public-2
................................................................................................................................................................................... 207
Table 5.3-14 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at away fans ........... 208
Table 5.3-15 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at away fans ... 208
Table 5.3-16 Los Angeles Memorial Coliseum EASE simulation input data ........................................................... 212
Table 5.3-17 Los Angeles Memorial Coliseum EASE simulation scenario-1 total SPL at listeners seats ................ 214
Table 5.3-18 Los Angeles Memorial Coliseum EASE simulation scenario-2 total SPL at listeners seats ................ 216
Table 5.3-19 Los Angeles Memorial Coliseum EASE simulation first arrival calculation at listeners seats ............ 217
Table 5.3-20 Los Angeles Memorial Coliseum EASE simulation C7 calculation at listeners seats ......................... 219
Table 5.3-21 Los Angeles Memorial Coliseum EASE simulation C50 calculation at listeners seats ....................... 221
Table 5.3-22 Los Angeles Memorial Coliseum EASE simulation C80 calculation at listeners seats ....................... 223
Table 5.3-23 Los Angeles Memorial Coliseum EASE simulation Articulation loss of consonants calculation at
listeners seats ............................................................................................................................................................. 224
Table 5.3-24 Los Angeles Memorial Coliseum EASE simulation speech transmission index (STI) at listeners seats
................................................................................................................................................................................... 226
Table 6.2-1 Los Angeles Memorial Coliseum redesign-1 EASE material list .......................................................... 232
Table 6.2-2 Los Angeles Memorial Coliseum design modification-1EASE simulation scenario-1 total SPL
calculation at listeners seats ....................................................................................................................................... 236
Table 6.2-3 Los Angeles Memorial Coliseum design modification-1 scenario-2 EASE simulation total SPL at
listeners seats ............................................................................................................................................................. 238
Table 6.2-4 Los Angeles Memorial Coliseum design modification-1 first arrival calculation at listeners seats ....... 239
Table 6.2-5 Los Angeles Memorial Coliseum design modification-1 EASE simulation C7 calculation at listeners
seats ........................................................................................................................................................................... 241
29
Table 6.2-6 Los Angeles Memorial Coliseum design modification-1 EASE simulation C50 calculation at listeners
seats ........................................................................................................................................................................... 243
Table 6.2-7 Los Angeles Memorial Coliseum design modification-1 EASE simulation C80 calculation at listeners
seats ........................................................................................................................................................................... 245
Table 6.2-8 Los Angeles Memorial Coliseum design modification-1 EASE simulation Articulation loss of
consonants calculation at listeners seats .................................................................................................................... 246
Table 6.2-9 Los Angeles Memorial Coliseum design modification-1 EASE simulation speech transmission index
(STI) calculation at listeners’ seats ............................................................................................................................ 247
Table 6.3-1 Los Angeles Memorial Coliseum design modification-2 EASE material list ........................................ 250
Table 6.3-2 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-1 total SPL
calculation at listeners seats ....................................................................................................................................... 254
Table 6.3-3 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-2 total SPL
calculation at listeners seats ....................................................................................................................................... 256
Table 6.3-4 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-1 total SPL
calculation at listeners seats ....................................................................................................................................... 259
Table 6.3-5 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-2 total SPL
calculation at listeners seats ....................................................................................................................................... 261
Table 6.3-6 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 first arrival
calculation at listeners seats ....................................................................................................................................... 262
Table 6.3-7 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 first arrival
calculation at listeners seats ....................................................................................................................................... 263
Table 6.3-8 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C7 calculation at
listeners seats ............................................................................................................................................................. 265
Table 6.3-9 Los Angeles Memorial Coliseum deign modification-2 EASE simulation setup-2 C7 calculation at
listeners seats ............................................................................................................................................................. 267
Table 6.3-10 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C50 calculation at
listeners seats ............................................................................................................................................................. 269
30
Table 6.3-11 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C50 calculation at
listeners seats ............................................................................................................................................................. 271
Table 6.3-12 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C80 calculation at
listeners seats ............................................................................................................................................................. 273
Table 6.3-13 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C80 calculation at
listeners seats ............................................................................................................................................................. 275
Table 6.3-14 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 Articulation loss of
consonants calculation at listeners seats .................................................................................................................... 276
Table 6.3-15 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 Articulation loss of
consonants calculation at listeners seats .................................................................................................................... 277
Table 6.3-16 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 Speech
Transmission Index calculation at listeners seats ...................................................................................................... 278
Table 6.3-17 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 Speech
Transmission Index calculation at listeners seats ...................................................................................................... 279
Table 6.4-1 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 at student
section- 1, student section- 2 ..................................................................................................................................... 281
Table 6.4-2 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 at student
section- 1, student section- 2 ..................................................................................................................................... 282
Table 6.4-3 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 at general
public- 1, general public- 2 ........................................................................................................................................ 283
Table 6.4-4 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 at general
public- 1, general public- 2 ........................................................................................................................................ 284
Table 6.4-5 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 at Titantron- 1,
Titantron- 2 ................................................................................................................................................................ 285
Table 6.4-6 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 at Titantron- 1,
Titantron- 2 ................................................................................................................................................................ 286
Table 6.4-7 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 at Southwest
corner, Press box-1 .................................................................................................................................................... 287
31
Table 6.4-8 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 at Southwest
corner, Press box-1 .................................................................................................................................................... 288
Table 6.4-9 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 Maximum,
Minimum & Average ................................................................................................................................................. 289
Table 6.4-10 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 Maximum,
Minimum & Average ................................................................................................................................................. 290
Table 6.4-11 Los Angeles Memorial Coliseum EASE simulation comparison of C7 at student section- 1, student
section- 2 ................................................................................................................................................................... 293
Table 6.4-12 Los Angeles Memorial Coliseum EASE simulation comparison of C7 at general public- 1, general
public- 2 ..................................................................................................................................................................... 294
Table 6.4-13 Los Angeles Memorial Coliseum EASE simulation comparison of C7 at Titantron- 1, Titantron- 2 .. 295
Table 6.4-14 Los Angeles Memorial Coliseum EASE simulation comparison of C7 at Southwest corner, Press box-1
................................................................................................................................................................................... 296
Table 6.4-15 Los Angeles Memorial Coliseum EASE simulation comparison of C7 Maximum, Minimum &
Average...................................................................................................................................................................... 297
Table 6.4-16 Los Angeles Memorial Coliseum EASE simulation comparison of C50 at student section- 1, student
section- 2 ................................................................................................................................................................... 299
Table 6.4-17 Los Angeles Memorial Coliseum EASE simulation comparison of C50 at general public- 1, general
public- 2 ..................................................................................................................................................................... 300
Table 6.4-18 Los Angeles Memorial Coliseum EASE simulation comparison of C50 at Titantron- 1, Titantron- 2 301
Table 6.4-19 Los Angeles Memorial Coliseum EASE simulation comparison of C50 at Southwest corner, Press box-
1 ................................................................................................................................................................................. 302
Table 6.4-20 Los Angeles Memorial Coliseum EASE simulation comparison of C50 Maximum, Minimum &
Average...................................................................................................................................................................... 303
Table 6.4-21 Los Angeles Memorial Coliseum EASE simulation comparison of C80 at student section- 1, student
section- 2 ................................................................................................................................................................... 305
Table 6.4-22 Los Angeles Memorial Coliseum EASE simulation comparison of C80 at general public- 1, general
public- 2 ..................................................................................................................................................................... 306
32
Table 6.4-23 Los Angeles Memorial Coliseum EASE simulation comparison of C80 at Titantron- 1, Titantron- 2 307
Table 6.4-24 Los Angeles Memorial Coliseum EASE simulation comparison of C80 at Southwest corner, Press box-
1 ................................................................................................................................................................................. 308
Table 6.4-25 Los Angeles Memorial Coliseum EASE simulation comparison of C80 Maximum, Minimum &
Average...................................................................................................................................................................... 309
Table 6.4-26 Los Angeles Memorial Coliseum EASE simulation comparison of first arrival timings at listeners seats
................................................................................................................................................................................... 311
Table 6.4-27 Los Angeles Memorial Coliseum EASE simulation comparison of Articulation loss of consonants at
listeners seats ............................................................................................................................................................. 312
Table 6.4-28 Los Angeles Memorial Coliseum EASE simulation comparison of speech transmission index at
listeners seats ............................................................................................................................................................. 313
Table 6.4-29 Los Angeles Memorial Coliseum performance ranking of all iterations by acoustic metrics .............. 317
Table 6.5-1 Los Angeles Memorial Coliseum performance ranking of all iterations by acoustic metrics ................ 320
Table 7.3-1 USC Trojans college football 2017-18 season schedule and results (University of Southern California
Athletics, 2018) ......................................................................................................................................................... 328
Table 7.6-1 Los Angeles Memorial Coliseum performance ranking of all iterations by acoustic metrics ................ 335
Table C.2-1 Sample Excel sheet spreadsheet export from Sound Analyzer app ....................................................... 359
33
Chapter 1: Introduction
1.1 Overview
Acoustic performance of a stadium can be simulated and validated by first performing a field study and
then comparing with simulated results. With trust established in the software, design changes can be made virtually
to predict the performance if the changes were to be implemented. The Los Angeles Memorial Coliseum is taken as
the case study. The Coliseum was visited during the USC Trojans football season 2017-18 to collect data during the
football games. For simplification purposes in developing the Dynamo script, the Harris Hall courtyard at University
of Southern California was as the first case study for its similarity to the Coliseum in terms of spatial configuration.
Both the spaces are enclosed on the sides with open to sky in the middle.
Chapter 1 describes the basic concepts of computer aided design (CAD), building information modeling
(BIM), visual programming, architectural acoustics, acoustic simulation software, and acoustic measurement
equipment.
1.2 Computer aided design, building information modelling, and visual programming
Computer aided design (CAD), building information modeling (BIM) and visual programming principles are
described in the following sections. A brief introduction to Revit, Dynamo, Rhinoceros, Grasshopper, Generative
Components, and Marionette is given.
1.2.1 Computer aided design
Computer aided design (CAD) generally refers to drafting programs that are intended to produce two-
dimensional drawings of buildings, vehicles, mechanical parts, layouts (Kensek, 2014). CAD programs comprise of
objects- lines, circles, splines, ellipses, rectangles and others that are defined by parameters and formulae (Kensek,
2014). CAD is vector based where editing is done at the object level (Kensek, 2014). Only limited type of geometric
information can be derived such as length, area, perimeter (Kensek, 2014). Any change or modification in the design
will take a long time to incorporate as CAD programs are only two dimensional and can be used as a drafting tool.
1.2.2 Building information modeling
Architecture, engineering, construction (AEC) professionals use building information modeling (BIM) to
efficiently manage the design, construction, and managing phases of their projects (Autodesk, 2018). Building
34
information modeling (BIM) provides an upgrade over computer aided design (CAD) by associating data with
geometry (Autodesk, 2018). For example, a line or surface in a 2d CAD drawing will only contain geometric data
while a BIM component could have data such as material, cost, manufacturer, etc. in addition to the 3d geometric
data. Building information modeling (BIM) professionals build their projects virtually into the program with all the
data which makes it more efficient than CAD. A building information model will have all the necessary construction
document (CD) setup in the model where any change made in the model is incorporated on all the sheets. The
parametric feature in building information modeling has enabled professionals to make better design decisions faster
as any changes made can be visualized immediately. Collaborating with mechanical, engineering, plumbing (MEP)
professionals is made easier by using building information modeling practices (Autodesk, 2018). Heating,
ventilation, air conditioning (HVAC), piping systems are modelled into the BIM model which can be used to detect
the clashes between the various building systems and make necessary changes to the system design. This helps the
professionals save time and expedite the project delivery process (Autodesk, 2018).
1.2.3 Visual programming
Visual programming is programming using visual illustrations or nodes instead of text; the resulting
program looks like a flow chart where nodes are connected in to perform specific tasks. Most computational design
environments are visual programming based but some programs allow users to manually write codes to perform
tasks. Visual programming allows user to assemble codes to perform tasks rather than writing code (Kilkelly, 2016).
Visual programming does not require the user to know writing code in computer language; users can develop a
visual program by developing a flow chart of the entire process. Outputs from one node are connected to inputs on
another (Kilkelly, 2016). A visual program contains a sequence of nodes, which are connected to show a graphical
representation of the steps taken to achieve the final design (Kilkelly, 2016). Grasshopper (in Rhino), Dynamo (in
Revit), Generative Components (with Microstation), and Marionette (in Vectorworks) are examples of visual
programming software.
Rhinoceros & Grasshopper
Grasshopper is an algorithmic modeling tool for Rhinoceros or Rhino 3D, the 3D modeling software by
Robert McNeel and Associates. Grasshopper has an extensive library of nodes and works as a graphical algorithmic
35
editor which is integrated into Rhinoceros modelling tools (Davidson, Scott;, 2018). Grasshopper can be used to
develop 3d models in Rhinoceros using visual programming.
Grasshopper has many supporting packages that perform simulations of various factors affecting building
performance. Ladybug is a Radiance based daylighting simulation tool while Honeybee is an Energy Plus based
energy simulation package designed for Grasshopper. Ladybug and Honeybee have a set of nodes that can be used
to perform energy and daylight analysis with parametric design capability of Grasshopper.
Pachyderm is an acoustic simulation tool that is an add-in to Grasshopper similar to Radiance and
Honeybee (Fig. 1.2-1).
Figure 1.2-1 Pachyderm script in Grasshopper to simulate acoustics for a room (McNeel Associates, 2018) .
Revit & Dynamo
Revit is a building information modeling (BIM) software developed by Autodesk that is widely used by
architects, landscape architects, structural designers, contractors and engineering professionals (Autodesk Inc,
2018). Revit helps architects develop the design from the conceptual design to construction documents (Autodesk
Inc, 2018). Revit can create perspectives, axons, elevations, plans, and other drawings from the building database
(Fig. 1.2-2).
36
Figure 1.2-2 Revit model of a single-family residence
Dynamo is a visual programming tool developed by Autodesk. It is available as a free version that is linked
to Revit and available as a stand-alone version (Kilkelly, 2016). Dynamo was developed to provide additional
support to existing features of Revit without having to access the Revit API (application programming interface)
directly.
Nodes are objects that are connected to form a visual program (Autodesk, Dynamo primer, 2018). Each
node will perform an operation depending on the intended operation. Nodes can be used to input data, parameter or
extract surface, information or perform arithmetic functions etc. (Autodesk, 2018). The anatomy of a node is as
follows (Fig. 1.2-3):
1. Name- Name of the node,
2. Main body of the Node- Right-clicking here will provide options which will have control over the
Node
3. Ports (In and Out) - The receptors for wires that supply the input data to the Node are in the left side
and the output ports are on the right side,
4. Lacing Icon- Indicates the Lacing option specified for matching list inputs,
5. Default Value- can be accessed by right clicking on the Node. Some Nodes have a default value
(Autodesk, 2018).
37
Figure 1.2-3 Anatomy of a node (Autodesk, 2018)
Wires connect between nodes to establish a relationship and flow of the visual program (Autodesk,
Dynamo primer, 2018). The wires are created by clicking on a port of one node to another (Fig 1.2-4). The visual
program sequence goes from left to right where the wires are connected from the output of the first node to the input
of the second node to follow the sequence.
Figure 1.2-4 Wiring of nodes in Dynamo (Kensek, 2017)
For example, a Dynamo script can create a grid of circles (Fig. 1.2-5). The first part of the script creates a
range of numbers using the “Range” node. A “Number” node is used to give inputs for the start and step in the
“Range” node. The “Number Slider” node is used to input the end in the “Range” node. The “cross product” option
is chosen under lacing by right clicking on the “Point.By.Coordinates” node. This option will create a cross field of
points based on the given range. In this case the range is from 0-100 with an interval of 10 which has 11 points
creating a field of 121 points.
38
Figure 1.2-5 Dynamo script creating a grid of circles (Kensek, 2017)
By using this method, it allowed that there could be modifications made to the script. For example, changes
in the range, radius of the circle etc. these nodes will change the output of the nodes respectively making it
parametric (Fig. 1.2-6).
Figure 1.2-6 Dynamo script showing the nodal network to create a grid of circles (Kensek, 2017)
Dynamo also has an integrated Python module that allows users the ability to create their own custom
nodes. Custom nodes are nodes that are created by users to perform specific functions that are not available in the
existing library (Autodesk, 2018). Custom nodes in Dynamo can be made in two ways. One by creating a visual
39
script with existing nodes and combine them all into a single node (Autodesk, 2018). The other method is to
manually script the nodes using programming language Python (Autodesk, 2018).
Dynamo has also an open source network of packages that are available through the Dynamo package
manager. Packages are a set of custom nodes created by the Dynamo online community. These packages are created
by Dynamo users who also share their new packages and improve based on another member’s feedback (Autodesk,
2018). Acoustamo is one similar package that was developed to simulate acoustic ray tracing in Dynamo. Lunchbox
is another Dynamo package that has many nodes that provide useful functionality on Revit models.
Generative Components
Generative Components was developed by Bentley systems (Bentley, 2017). It was first introduced in 2003
and commercially released in 2007 (Kilkelly, 2016). Generative Components works with Microstation software
though a stand-alone version is available Users can develop their models by directly manipulating the geometry or
by using the visual programming interface to develop an algorithm to model the complex form (Bentley, 2017).
Generative Components supports many industry standard file input and outputs including DGN by Bentley Systems,
DWG by Autodesk, STL (Stereo Lithography), Rhino (Bentley, 2017). Generative Components can also integrate
with building information modeling systems, specifically and an installed extension/Companion Feature to Bentley's
AECO sim Building Designer (Bentley, 2017). The interface has several windows (Fig. 1.2-7). The first window
shows the rendering window which shows the model with rendered materials. The second window shows the
engineering window that has illustrations based on simulations. The relationship window shows the nodal network
that shows the visual programming interface.
40
Figure 1.2-7 Generative Components Interface (Bentley, 2017)
Marionette
Marionette is the visual programming add-in for Vectorworks (Fig 1.2-8). Marionette is built directly into
Vectorworks. It works on both the Macintosh and Windows operating systems (Kilkelly, 2016). Marionette allows
the user to manipulate Vectorworks objects using visual programming without learning a text-based language
(Vectorworks, 2017).
Figure 1.2-8 Marionette visual scripting interface (Frausto-Robledo, 2015)
1.3 Architectural Acoustics
Before developing a Dynamo script to simulate acoustics, it was necessary to understand the basic concepts
of architectural acoustics. The following sections will briefly describe the concepts of geometric acoustics (GA),
sound reflection, sound diffraction, sound absorption, sound transmission, sound loss. A short description of the
41
common acoustic parameters that are calculated using acoustic simulation tools are explained in the following
section.
Architectural acoustics is the science of sound performance within buildings (Long, 2006). Sound control
can create a sonic environment in where ideal conditions can be provided in enclosed and open spaces (Doelle,
1964). It should also provide adequate protection against excessive noise and vibrations which in turn aid the user’s
productivity and well-being (Doelle, 1964). Sound control has two main goals, one is to provide proper room
acoustics, which controls the effective sound production, transmission and perception of wanted sounds and
accentuate them for listening (Doelle, 1964). The other goal is to provide noise control, which is to remove the
unwanted noise coming from structure, mechanical equipment etc. that can affect the user.
1.3.1 Geometric Acoustics
Geometric acoustics (GA) is a simpler approach in architectural acoustics where users consider the
behavior of sound rays similar to light rays (Doelle, 1964). Imaginary sound rays similar to the light rays
perpendicular to the advancing wave front, travelling in straight lines in every direction of the space are considered
(Doelle, 1964). The sound rays are considered to carry sound energy, part of the energy will be reflected, part of the
energy will be absorbed by the surfaces, part of the energy is transmitted through the structure (Doelle, 1964).
1.3.2 Sound reflection
Hard, rigid surfaces reflect most of the incident sound energy (Fig 1.3-1). Sound reflects similar to light
(Long, 2006). Angle of incidence will be equal the angle of reflection similar to light (Long, 2006). This principle
applies only to planar surfaces. Concave surfaces concentrate the sound rays on reflection while the convex surfaces
will disperse the rays on different direction (Doelle, 1964).
42
Figure 1.3-1 Behavior of sound in an enclosed space 1. Incident sound, 2, direct wave front, 3. Reflected sound, 4. Reflected
wave front, 5. Sound transmitted through the enclosure, 6. Sound absorbed at wall surface, 7. Sound absorbed in the air, 8.
Sound energy dissipated within the structure, 9. Structure-borne sound conducted to other parts of the building, 10. Sound
radiated by flexural vibration of the enclosure, 11. Acoustic shadow, 12. Diffraction of sound through opening, 13. Multiple
sound reflection contributing to reverberation, 14. Diffused sound through surface irregularities (Doelle, 1964)
1.3.3 Sound diffraction
The phenomenon of sound waves bending and scattering around obstacles is called diffraction (Doelle,
1964). Obstacles can include beams, columns, structural members, walls etc. (Doelle, 1964). Lower frequency rays
bend more due to diffraction.
1.3.4 Sound absorption, absorption coefficient
Soft, porous materials absorb a portion of the sound bouncing or falling on them and are called absorbers
(Long, 2006). Sound absorption happens when sound energy changes into another form of energy mostly heat while
sound rays fall or transmit through the surface. Heat produced through sound absorption is small.
43
Every material absorbs sound to an extent, however there are some materials specifically used for sound
absorption in auditoriums, halls, theaters etc. called acoustical materials (Doelle, 1964). The sound absorption
efficiency of a material is rated by sound absorption coefficient. The sound absorption coefficient is the ratio of
fraction of the incident sound energy absorbed to the reflected sound energy from the surface (Doelle, 1964). The
value of sound absorption coefficient varies from 0-1. If a material absorbs 70% of the incident sound energy and
reflects 30%, the sound absorption coefficient of the material is 0.70. An opening in a building will have an
absorption of 1.0. Sound absorption coefficient is denoted by α. The sound absorption coefficient for a material
varies with frequency (Long, 2006).
1.3.5 Sound diffusion
Sound diffusion is important in a space as similar sound pressure in all parts of the room will create a
uniform sound field (Doelle, 1964). Adequate sound diffusion provides uniform distribution of sound in a space.
Sound diffusion accentuates natural speech, music qualities and prevents various acoustical defects (Doelle, 1964).
Sound diffusion can be achieved by scattering elements, surface irregularities, sound absorption treatments, irregular
and random distribution of sound absorption treatments (Doelle, 1964).
1.3.6 Sound growth and decay, reverberation time
The sound pressure level of a sound generated in an enclosed space will increase to a maximum until it
reaches a steady state maximum. A diffused sound field will spread the sound uniformly through the space. This
happens due to the reflections of the sound waves with the surfaces of the space (Long, 2006). The prolongation of
sound due to successive reflections within an enclosed space after switching off the source is called reverberation
(Doelle, 1964). There will be a noticeable time before the sound dies when the source has been stopped.
Reverberation time is the time taken for the sound pressure level to drop 60 dB after the source is stopped.
W.C. Sabine developed an equation to calculate reverberation time by establishing a relationship between
the volume of the room with the total sound absorption (Doelle, 1964). The Sabine’s formula for calculating
reverberation time is 𝑅𝑇 (60) = 0.049 𝑉 /(Ʃ𝑆𝛼 ) where RT(60) is the reverberation time in seconds, V is the volume
of the space in cubic feet, S is the surface area in square feet, α is the absorption coefficient of material at a given
frequency, Ʃ is the summation of S times the α for all surfaces (Egan, 1988).
44
1.3.7 Acoustic parameters which define the acoustic quality of a space
Acoustic simulation programs can calculate a set of parameters that help in defining the acoustic quality of
a space. The following section describes the parameters and their tangible and intangible effects on overall acoustic
performance of the space.
Direct Sound Pressure Level (SPL), Total Sound Pressure Level (SPL)
Acoustic simulation software provides a mapping of the Total Sound Pressure Level (SPL) of the space
with the direct rays and the reflections in the space (ADA (Acoustic Design Anhert), 2009). Direct SPL mapping
calculates only the direct sound from the sources without any reflections (ADA (Acoustic Design Anhert), 2009).
L7, L50, L80:
Ln is the noise level exceeded for n% of the measurement time. “n” is a percentile value that can vary from
1 to 99 (Castle Group Ltd, 2018). Advanced sound pressure level meters can measure sound in percentiles. Each
percentile values helps in analyzing the noise levels. L10 is the nose level exceeded for 10% of the measurement
duration (Fig 1.3-2) (Castle Group Ltd, 2018).
Figure 1.3-2 Percentile values of Ln (Castle Group Ltd, 2018)
45
Clarity (C), C7, C50 and C80
Clarity in acoustics is a parameter to evaluate the degree of separation of successive sounds. It is a ratio of
the early sound to the reverberant sound after a certain amount of time (ADA (Acoustic Design Anhert), 2009).
C7 is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct
sound field (ADA (Acoustic Design Anhert), 2009). Values above -15 dB are considered good. Values closer to 0
dB are considered better (ADA (Acoustic Design Anhert), 2009).
C50 measures the speech clarity which is the ratio between the early and late reflections in a space after 50
ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic
Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation (ADA
(Acoustic Design Anhert), 2009).
C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space.
Speech Transmission Index (STI)
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009).
Loudspeaker overlaps
Acoustic simulation software can calculate the number of speakers that overlap at any location in a space.
This will help in design of loudspeaker systems and help in spreading them evenly within the space. It is
recommended not to have more than 1.0 - 1.5 speakers overlapping at any location while designing an audio system
for a space.
Arrival Time
Acoustic simulation software can calculate the arrival time for any location from the nearest sound source.
This will help in design of audio systems to evenly spread out the speakers to have desired sound delay in the space.
For 20 feet, recommended maximum arrival time is 17.9 microseconds (GB Audio, 2018).
46
1.4 Stadium acoustics
Los Angeles Memorial Coliseum is used as the case study for analyzing stadium acoustics. A major
difference between architectural acoustics and stadium acoustics is that the spatial configuration of most stadiums
varies from other spaces that are given acoustic treatment. Many stadium spaces, like the Coliseum are enclosed on
all sides but often open to air above. Most stadiums are designed to be provide a loud environment. Home team fans
try to intimidate the opponent team with noise. The shape of the stadium, audience capacity, roof configuration, and
placement of sound systems all play a major role in stadium acoustics.
1.4.1 Shape, seating and roof configuration
Most sports arenas in Europe are engineered to amplify sounds by using partial roofs (Daftardar, 2016).
The partial roofs help in reflecting towards the pitch and audience to amplify crowd noise. Wood and metal can be
used to increase reverberations in a stadium (Daftardar, 2016). Empty space under wood seating helps in
reverberating sound throughout the structure. Optimum sound levels can be achieved by adding more reflective
surfaces on the stadium.
Al Bayt stadium in Qatar, which is currently under construction for the 2022 FIFA World Cup, is designed
based on tent shaped structure (Daftardar, 2016). The tent shaped structure reflects the sound inside the stadium in a
highly controlled manner. The Los Angeles Memorial Coliseum has an open bowl shape with no partial roofs over
the audience stands.
1.4.2 Sound and distance
It is also essential to design sound systems in stadiums in a way that the speakers are distributed evenly
throughout the space. Longer distances between audience and speaker systems will induce speech intelligibility
issues. The most effective way of achieving acceptable speech intelligibility is to use a distributed sound system
with no seat being more than about 80 feet from the nearest loudspeaker.
1.5 Acoustic simulation software
ODEON, Ecotect, REW- Room EQ Wizard, EASE – Enhanced Acoustic Simulator for Engineers, Sound
Plan essentials, Catt-Acoustics are some of the acoustic simulation tools are available in the market and are widely
47
used among the acoustic designers and the engineering firms (Table 1.5-1). Pachyderm is an add-on plugin that
works with Grasshopper to perform acoustic analysis for Rhinoceros 3D.
S.No Software Website
Cost (As of
March
2018)
Primary acoustic usage
1
EASE- Enhanced
Acoustic Simulator
for Engineers
http://ease.afmg.
eu/index.php/software-
new.html
$2590
And above
Acoustic simulation of rooms,
stadiums, office spaces etc.
2. ODEON https://odeon.dk/
$5200 and
above
Acoustic simulation of concert halls,
commercial spaces, airports,
3. CATT-Acoustics
https://www.catt.
se/
$2500 and
above
Acoustic simulation of rooms,
stadiums, office spaces etc.
4. Pachyderm
http://www.persp
ectivesketch.com/pachyde
rm/index.php
Free
Acoustic simulation addon with
Grasshopper, works with Rhino
5.
REW- Room EQ
Wizard
https://www.roo
meqwizard.com/
Free
Acoustic simulation of spaces and
signal generator to measure acoustic
performance
6.
Sound Plan
Essentials
http://www.soun
dplan.eu/english/products-
and-services/soundplan-
software/
$2900
Acoustic simulation of large scale
infrastructure such as Roads,
Highways.
Table 1.5-1 Acoustic simulation software available in the market
1.5.1 EASE- Enhanced Acoustic Simulator for Engineers
Enhanced Acoustic Simulator for Engineers (EASE) software is a design and analytic computer application
that is used in the optimization of acoustics. Through its capability to execute 3-D and complex mathematic
analyses, EASE is useful for the acoustic simulation of stadiums since it offers ease of use, accessibility, and
features that allow the users to obtain their required analyses. It uses a CAD software program to edit as well as
export or important data and files in addition to conducting reverberation time calculations (Fig. 1.5-1). The
software is also fitted with loudspeaker database to determine the level of the sound and customization to ensure that
the stadium designers obtain information on the right material to use during the construction of the stadium (AFMG
Technologies GmbH, 2018). Additional aspects contained in the EASE software include statistical models, arrays
and clusters, sound systems, standard mapping, evaluation of decay, and acoustic material database (AFMG
Technologies GmbH, 2018).
48
Figure 1.5-1 Editing model in EASE
1.5.2 Odeon
Odeon is an acoustic simulation software used for prediction of room acoustics and public-address (PA)
systems in concert, opera halls, and other public spaces (Odeon A/S, 2017). It can simulate acoustic conditions for
complex geometric spaces. Results come as acoustic parameters, sound mapping, binaural or surround auralisation
that can be used to analyze the results. Results can be exported as images, Excel spreadsheets (.xlsx), which can be
used for presentation and analysis. It is widely used by acousticians (Fig. 1.5-2).
Figure 1.5-2 Odeon simulation of the Boston symphony hall (Odeon A/S, 2017)
49
1.5.3 CATT-Acoustics
CATT-Acoustic was developed in Goeteborg, Sweden by Bengt-Inge Dalenbaeck (CATT-Acoustic, 2017).
CATT is an acronym for Computer Aided Theater Technique as the company’s first products were décor CAD
programs in 1986 (CATT-Acoustic, 2017). It is a comprehensive software room acoustics modeling tool, which can
do prediction in high fidelity (CATT-Acoustic, 2017). It can do the simulation of a room with variable sound
sources as well as surfaces (CATT-Acoustic, 2017) (Fig. 1.5-3). Based on its specific algorithm, it can accurately
predict the acoustic performance of the space before built and provide realistic auralisation (CATT-Acoustic, 2017).
Auralisation is converting the electro acoustic data generated by acoustic simulation software into an audio
signal. An audio filter is created from the input data and the audio file (usually a .wav file) is processed to give a
realistic binaural auralisation. Binaural auralisation gives output for both left and right ears while mono auralisation
gives a single output signal.
Figure 1.5-3 Acoustic simulation of an auditorium using CATT-Acoustic (CATT-Acoustic, 2017)
1.5.4 Pachyderm
Pachyderm is an add-in to Grasshopper. Pachyderm Acoustic started as the master thesis work of Arthur
van der Harten as a platform with which to explore new ideas in acoustics simulation (Grasshopper, 2017). In 2008,
the software was first published online as Pachyderm Acoustic (Grasshopper, 2017). It has since seen contributions
50
from a variety of individuals from many forms of practice in architecture and acoustics. It works based on the
principle of visual programming similar to Dynamo (Fig 1.5-4).
Figure 1.5-4 Pachyderm script in Grasshopper (McNeel Associates, 2018)
1.5.5 REW- Room EQ Wizard
Room EQ wizard (REW) is a free room acoustics analysis software for measuring and analyzing room and
loudspeaker responses (Room EQ Wizard, 2017). Room EQ wizard includes tools for generating audio test signals
(Fig. 1.5-5) measuring SPL and impedance, measuring frequency and impulse responses, generating phase, group
delay and spectral decay plots, waterfalls, spectrograms and energy-time curves, generate real time analyzer (RTA)
plots (Room EQ Wizard, 2017). Room EQ wizard can also calculate reverberation times, determine the frequencies
and decay times of modal resonances and automatically adjust the room acoustic settings of parametric equalizers to
match a target curve for and counter the effects of room modes (Room EQ Wizard, 2017).
51
Figure 1.5-5 Interface of REW (Room EQ Wizard, 2017)
1.5.6 SoundPLAN Essentials
SoundPLAN Essential was one of the very first noise modeling software programs on the market, debuting
in 1986 (Soundplan essentials, 2017). SoundPLAN Essential is used primarily to calculate noise levels received
from large scale infrastructure such as roads, railways, industry and parking lots. SoundPLAN Essential can provide
acoustic contour mapping for large scale infrastructure like a power plant facility (Fig. 1.5-6). SoundPLAN
Essential calculates noise emitted by various sources propagates and disperses over a given terrain (SoundPLAN
Acoustics, 2017).
Figure 1.5-6 Acoustic contour mapping in Soundplan essentials for a power plant facility (Soundplan essentials, 2017)
52
1.6 Acoustic measurement equipment and software
Bruel & Kjaer type 2250, Rolland octa capture, Audix TM-1, Yamaha stagepas 400i, Extech HD 600 were
the equipment used for the acoustic measurement. Acoustic measurement software EASERA was used to collect the
data from the equipment. Sound analyzer app was used in the mobile and Extech HD 600 sound pressure level meter
was used to collect data at the Coliseum as larger equipment were prohibited due to security reasons. The data sheet
of the acoustic measurement equipment can be found in Appendix A: Acoustic measurement equipment data sheet.
1.6.1 Acoustic measurement equipment
S.No
Make and Model Equipment Image
1.
Bruel & Kjaer
Type 2250
Sound Pressure
Level meter
(Bruel & Kjaer, 2018)
2. Audix TM-1
Sound testing
microphone
(Audix, 2018)
3.
Rolland
OCTACAPTURE
Portable
Amplifier
(Roland Corporation, 2018)
4.
Yamaha Stagepas
400i
Speaker system
(Yamaha Corporation, 2018)
5. Extech HD 600
Sound Pressure
Level meter
(FLIR Systems, 2018)
Table 1.6-1 Acoustic measurement equipment
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1.6.2 Acoustic measurement software
In addition to the acoustic measurement equipment, EASERA and Sound Analyzer app programs were
used to collect data during the acoustic field study.
EASERA
EASERA is used by acoustic consultants for measuring data on field. EASERA can be setup with any
acoustic measurement equipment to collect data (Fig. 1.6-1). It can also collect data using the microphone available
in the PC or laptop.
Figure 1.6-1 EASERA collecting live acoustic data using the laptop microphone
Sound Analyzer app
Sound Analyzer app is a mobile application available on Android play store. It collects data based on Octa
band frequencies, 1/3 octa band frequencies using the mobile microphone (Fig 1.6-2) (Fig 1.6-3). It also has a
calibration feature which can be used to calibrate the device with an actual Sound Pressure Level meter. The
collected data can be exported as Excel files (.xlsx) and images.
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Figure 1.6-2 Screenshot of live data collection using Sound Analyzer app
Figure 1.6-3 Google Pixel mobile device (Amazon, 2018)
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1.7 Glossary of terms and abbreviations
A glossary of terms and abbreviations is provided for the most common terminology.
1.7.1 Glossary of terms
A-Weight - the standard frequency weighting to simulate the response of the human ear at moderate levels
(Egan, 1988).
C-weight – the standard frequency weighting to stimulate the response of the human ear to loud noise
(Egan, 1988).
Decibels - logarithmic ratio of measured power to a reference power (Cowan, 1994).
Equivalent-Continuous Sound Level (Leq) - the level of constant sound, expressed in dB, which in a given
time period has the same energy as does a time varying sound (Egan, 1988).
Frequency - the measure of vibrations per second of air in which sound is transmitting; frequency is
measured in Hertz (Hz) (Cowan, 1994).
Hertz - measurement of frequency (Egan, 1988).
Intensity - the magnitude of sound, related to the perception of loudness (Cowan, 1994).
Noise - “sound unwanted by the listener” (Taylor, 2016)
Peak - “the maximum value of the instantaneous, frequency weighted, sound pressure in a given time
interval.” (Taylor, 2016)
Resonance - an increase in sound due to reflection of an acoustic wave (Egan, 1988)
Sound - “the propagation, transmission and reception of waves in some medium, most commonly air”
(Taylor, 2016)
Sound Pressure Level - the measure of the air vibrations that make up sound; sound pressure level is
measured in decibels (dB) (Cowan, 1994).
Speed of Sound - the distance sound travels in a given medium per unit time; the speed of sound in air is
344 m/s (Egan, 1988).
Temporary Threshold Shift - a temporary shift in the auditory threshold, resulting in temporary hearing loss
(Cowan, 1994).
Time Weighted Average - “the level of a constant sound, expressed in dB, which in a given time period
would expose a person to the same noise dose as the actual sound over the same period.” (Taylor, 2016)
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1.7.2 Abbreviations
dB – Decibels (Taylor, 2016)
dBA – Decibels (A-weighting) (Taylor, 2016)
dBC – Decibels (C-weighting) (Taylor, 2016)
Hz- Hertz (Taylor, 2016)
LAeq – Equivalent Continuous level; also written as dBA Leq. (Taylor, 2016).
LA max – Maximum Sound Level; also written as dBA Max. (Taylor, 2016).
Leq – Equivalent Continuous Sound Pressure level; One Minute-Mean Noise Level in dBA (Taylor, 2016)
SLM – Sound Level Meter (Taylor, 2016)
SPL – Sound Pressure Level (Taylor, 2016)
TWA – Time weighted Average (Taylor, 2016)
USB – Universal Serial Bus (Taylor, 2016)
1.8 Summary
Chapter 1 gave a brief introduction to concepts of computer aided design (CAD), building information
modeling (BIM) and visual programming. Revit, Dynamo, Rhinoceros, Grasshopper, Marionette, Generative
Components which are some of the software programs used in the industry were studied to look for developing the
research methodology.
Odeon, EASE, CATT-Acoustics, Pachyderm, REW and SoundPlan Essentials acoustic software programs
are used by acoustic professionals for acoustic simulation and acoustic measurements. Audix TM-1, Rolland
Octacapture, Yamaha Stagepas 400i, Bruel & Kjaer type 2250 are acoustic measurement equipment used for the
acoustic field study at Harris Hall courtyard. EASERA program was used to record the data and perform the analysis
with the equipment. Extech HD 600 and Sound Analyzer app are studied to learn about their usage and were used to
record data during the home football games at the Los Angeles Memorial Coliseum during the 2017-18 college
football season. EASE was used to simulate acoustics on courtyard and Coliseum. The courtyard was modelled in
Revit to develop the Dynamo script for simulating acoustics. EASE was used to validate the results from the
Dynamo script and the field study. EASE was used perform the acoustic simulation for the design modification
analysis of the Coliseum.
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Chapter 2: Literature Review
2.1 Overview
Chapter 2 delves into key concepts such as computational design, stadium acoustics, acoustic simulation,
and acoustic measurement. Relevant researches made by academicians on building information modeling (BIM),
visual programming, architectural acoustics, stadium acoustics and acoustic simulations are studied to streamline the
methodology and the possible bottlenecks that could be encountered.
2.2 Building information modeling, visual programing
Relevant researches made by academicians and professionals in the field of building information modeling
and visual programing on developing programs to calculate specific parameters in a building are were used to aid in
developing an algorithm for the Dynamo script.
2.2.1 Building information modelling
Building information modeling (BIM) can be used for performing daylight and energy simulations using
Revit and Dynamo (Mengana, Mousiadis, & Gudmundsson, 2016). A test building was constructed in Stockholm,
Sweden. It was formed in a way that allows various material parameters to be altered in order to study the impacts of
the annual energy distribution (Mengana, Mousiadis, & Gudmundsson, 2016). Dynamo was used to develop a script
to make parametric variations on the Revit model and run the simulations.
A software tool was developed by Chengde Wu and Mark Clayton (2013) to perform auralisation and
visualization of a Revit model (Wu & Clayton, 2013). An auditorium in Texas A&M university was chosen as the
case study and modelled in Revit. Building information modeling (BIM) data was extracted from the Revit model. A
frequency analysis module was developed that analyzed the data using a sample sound track and sorts out the
dominant frequency (Wu & Clayton, 2013). The software calculated reverberation time and sound intensity level
and applied it to the sample sound track to provide real time auralisation (Wu & Clayton, 2013).
2.2.2 Visual programming
There have been several research projects in the field of computational design to develop software tools to
calculate specific parameters that aid in the design of a part of the building system or the whole design.
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A study examined the potential of creating a performance-based design based on the parametric design
(Norton, Kensek, Noble, & Valmont, 2013). A former sound stage at University of Southern California used by
Thornton School of Music was taken as the case study. It was a multiuse space for orchestral, percussion, master
class and recital use (Norton, Kensek, Noble, & Valmont, 2013). The target acoustic metrics such as reverberation
time, bass ratio, and the early energy ratios of the clarity index and objective support for each programmatic use was
defined with the panelized ceiling being the design element. Based on the inputs, Grasshopper was run to identify
the optimal solution for the types of materials to be used on the panels on the ceiling (Norton, Kensek, Noble, &
Valmont, 2013).
Acoustamo was developed as a tool to simulate acoustic tracing in Dynamo by Andrea Vannini and
Michael Hudson (Autodesk, 2015). Acoustamo is a Dynamo package with a set of custom nodes which can perform
a ray tracing function on Revit models. Point source can be defined by location, direction parameters using the
directed ray custom node. Ray trace solver node drew a polycurve showing the sound propagation along the Revit
model based on the defined point source, direction and the number of bounces (Autodesk, 2015). Acoustamo could
only show the sound propagation in the Revit model and not perform any calculations.
2.3 Architectural acoustics
Research indicated that EASE enables the sound simulation by providing graphic displays, allocates
absorption of sound coefficients in the venues’ surfaces, and establishes the sources of sounds as well as posts to
listen (Moreno, 2013). The author describes the effectiveness of theater acoustic simulation using the software.
EASE software contains a comprehensive database of the construction material, even though designers can also add
material from the scattering and absorption coefficients that correspond to a 100-10000 Hz frequency range
(Moreno, 2013).
The analysis and findings by Boeck, Navvab, Heilman, and Bisegna (2012) was corroborated by another
one conducted by Golas and Suder-Debska (2009), who analyzed a dome hall theater’s acoustic field. According to
the authors, the use of simulations to model compartments allows designers to determine the acoustic distribution
using the graphic elements of a selected software. The authors in the case study was the Dome Home Hall of Theater
Groteska in Krakow, Poland (Suder-Debska & Golas, 2009). The analysis used the RAYNOISE software for
simulation. The software enabled them to forecast and analyze the acoustic conditions in the open spaces and closed
compartments of the theater.
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The geometrical methods used were the ray model and the image sources model. The assumption that the
models of the software work with are, first, that the reflection of waves complies with the Snell’s law, which
indicates that the angle of reflection is similar to the angle of incidence. The second basis of the assumption is that
the wave path that runs between two successive reflections is the section of a straight line. Lastly, the assumption of
the models is that the wave phenomena effects are neglected, that is through the diffraction, scattering, as well as the
superposition of the waves (Suder-Debska & Golas, 2009). The model calculated the involved RT through the
Sabine method as well as the echograms that were obtained when the software’s output of the simulation applied the
cone method.
2.4 Stadium acoustics
Several research projects have been made based on stadium acoustics on various factors affecting the
acoustic performance. The literature studies have been grouped based on noise emanating from the stadium, noise
made by the audience, and acoustic simulation of stadium spaces.
2.4.1 Noise emanating from the stadium
Stadiums have an impact on their local environment. It is important to consider that stadiums are often
constructed in cities, near residential areas, and other sections of a metropolitan area where the effect of noise may
be detrimental. Using the ICARE and MITHRA software, the authors simulated the level of noise emanating from
stadiums (Rougier, et al. 2010). To predict the sound (noise) levels in the areas surrounding the stadium, the authors
conducted multiple basic analyses. The first is the common use of stadiums, especially in the United States, for the
National Football Federation (NFL) matches. The important aspect is the characterization of a fan’s source in a
stadium. What the researchers aim to find here is the original, primary source of the sound, which, according to
multiple analyses, is a single supporter in the stadium. A supporter is a fan of the home team.
The other aspect provided by the authors is the sound power variations between the two stands in an
ordinary stadium, as well as factoring on the period taken to play the match. After determining the level of sound
produced by one supporter from the stadium, the analysis of the variation of sound shows that the sound level the
supporters’ stand is 8.5dB higher than the other stands. Since two, opposing, supporters are on the opposite stands
and emit 8.5dB of sound towards each other, the level of sound doubles and is thus useful in calculating the level of
sound obtained in a packed stadium when all the two stands are packed to capacity.
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Another aspect that should be considered is that stadiums are also used for music concerts. The loudest
source of sound heard around the stadium is from the music systems, not the audience attending the event. In most
cases, the speakers are arranged in a line array cluster that is used in the diffusion of sound in a homogenous manner
(Rougier, Defrance, Noe, Maillard, & Baulac, 2010). All the situations where a music concert or a football match is
played in the stadium results in sound level that affect the acoustic environment in the areas surrounding the
respective stadiums. When fans make noise inside the stadium from the two opposite stands, the reverberation
caused is high and the echo can be heard around the areas surrounding the stadium. A similar impact is experienced
during music concerts.
The simulation software can be used to measure the acoustic effects of the noise in the stadium through
applying statistical models and the inbuilt graphical modelling capabilities to understand the intensity of the noise
inside the stadium and the distance to which the sound can be felt around the stadium (Rougier, Defrance, Noe,
Maillard, & Baulac, 2010). The results can be used to determine whether the sound exceeds, or is within, the
recommended noise level in public places.
2.4.2 Stadium simulation
Semi-stadium systems
A study was conducted on the “ray chaos in an architectural acoustic semi-stadium system” (Yu and Zhang,
2013). The authors applied a dynamic model of position, angle, and side factors to study the acoustic ray chaos of
what they referred to as “semi-stadium systems” using the Lyapunov characteristic component used in dynamical
systems. The aim of using this model was to apply a quantity that features the separation rate of the infinitesimally
related trajectories (Yu & Zhang, 2013). In the study, the exponent was used to obtain a quantitative description of
the instability of the sound frequency. The main idea was that the sound simulation of stadiums brings a different
result depending on the shape of the stadiums, which indicate that the direction of noise also leads to different
results. The application of the analysis model used in the semi-circular stadiums chaotic dynamics simulations of the
acoustic aspects in an enclosed design stadium (Yu & Zhang, 2013)..
Acoustic modelling of stadiums
A report was presented at the International Congress on Acoustics on the computer simulations
performance for design acoustics (Vorlander, 2010). Using EASE, the author concluded that an appropriate acoustic
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model is important in the related simulations. The surface aspects of the simulations, which are often produced
polygons, are required to be larger than the wavelengths, which enable them to cover a large range of audio
frequency (Vorlander, 2010). Since attaining this is not viable, solutions that apply no theoretical basis are used in
the engineering computer software. It was recommended to use a lower resolution and lower frequencies in the CAD
model to accelerate the algorithm performance (Vorlander, 2010).
There is a gap in literature that comprehensively addresses the effect of material data in terms of
absorption coefficients on the prediction results using geometric acoustics (Vorlander, 2010). Apart from the data of
reflection factors and sound resistance, most of the available absorption coefficients are found in the unreliable
sources on the internet. The report concludes by indicating that the speed of computation is one of the most
important issues in the modelling of acoustics simulations for stadiums. Since most of the computer models have
been criticized for time and accuracy, as has been indicated by Vorlander, he recommends using the newly-
developed EASE software versions for acoustic simulations, since it has shown its effectiveness in the areas that it
has been used in the construction of sound acoustic models (Vorlander, 2010).
3d beamforming
The Michigan Stadium measurements involved various analyses including testing a sound system in an
unoccupied stadium. Through showing the data on the various frequencies, the researchers were able to depict the
reflection of sound on the opposite sections of the stadium (Navvab, Heilmann, & Sulisz, 2009). What the scholars
were investigating the significance of 3-D beamforming to understand the source of the noise in stadiums and where
it is loudest. The study found that the addition of glass gallery boxes in the University of Michigan stadium
increased the crowd noise during games. While the authors used the Acoustic Camera, the EASE software’s
usefulness is highlighted here through the way in which the CAD can be used to construct 3d models (Navvab,
Heilmann, & Sulisz, 2009).
2.4.3 Noise generated by fans
Navvab, Heilman, & Sulisz, 2009
Noise generated by fans and crowds in competitive matches is one of the major challenges faced by sport
organizers and the associated facilities’ managers (Navvab, Heilmann, & Sulisz, 2009). It is absolutely necessary for
the home team organizers to utilize the home advantage by creating a loud atmosphere in the stadiums. A louder
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atmosphere motivates the home team to perform better and creates an intimidating experience for the opponents,
which is part of taking home advantage in every sport. Such a situation has resulted in increased participation in the
sporting events and fan enthusiasm, even though sound intensity in stadiums is now measured at the rate of 95-110
dBA with sometimes peaking up to 115 dBA across all major sporting venues in the United States. Sound systems
are required to be at least 10 dBA louder than the audience to be heard. However, exposure to sound pressure levels
over 115 dBA over longer periods of time can cause hearing damages to fans. It is necessary to design a sound
system which could provide a balance between providing an intimidating atmosphere for the away teams and also
not expose the audience to higher sound pressure levels for longer periods of time. In the United States, for example,
there are regulations that need the compliance with the National Football League (NFL) provisions on fan or crowd
noise management. Similarly, the urban areas’ regulations on noise control are need of new approaches that will be
useful in gauging the environment hazards. Due to their changing range and categorization, the noise that the created
by the crowds have affected the results of matches, and in past analyses of data, increase in the case of noise-
associated punishments.
Vorlander, 2010
Since stadiums are subject to echoes and acoustics of high magnitude, it is important to understand how
they occur, their magnitude (minimum and maximum), and the best ways that architectural designs can be used to
ensure that the sounds in the stadiums are not problematic. To understand this, EASE provides a simulation platform
that architects can use alongside sound designers in the designing of stadiums (Vorlander, 2010). This literature
review offers an analysis of recent studies that have focused on the effectiveness of using the EASE software to
develop simulations that enable the understanding sound, and its impacts, on stadiums.
The accuracy of the acoustic simulation program can be checked by comparing the results with
measurement results. The reliability of the software is dependent on the input data which included the level of
detailing of the CAD model, material finishes, boundary conditions etc. The required level of detailing of CAD
model used for acoustic simulations vary depending on frequency ranges. Lower frequencies require lesser level of
detailing while the higher frequency ranges require higher level of detailing. The software programs provide color
scaled mappings and in-room auralisation. The author also states that none of the acoustic simulation packages allow
modelling of curved spaces. Curved surfaces are approximated by the number of planes.
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2.5 Acoustic simulation
Acoustic simulation programs can calculate acoustic parameters such as reverberation time, clarity, sound
pressure levels and provide real time auralisation which can be used to understand the acoustic performing quality of
the designed space. Researchers have found that here is a perceived difference in the software prediction and the
actual performance of the spaces.
2.5.1 EASE features
The findings by Moreno (2013) are supported by the PhD dissertation work conducted by Utami (2011).
According to the findings of Utami, stadiums are large venues with ellipse shapes, and the major acoustical issues in
such arenas include reverberation and room noise reflection, sound insulation and environmental noise impact, and
intelligibility of speech (Utami, 2011). EASE provides sufficient simulation toward the visualization of the path of
sound propagation from all the identified sources (Utami, 2011). EASE has an aural capability, enabling the
exposing the subjects to audio stimulus that created from the output of the simulation using the EASE software
(Utami, 2011). The significance of aural capability of the software is indicated as able to allow repeatability to
enable the survey of the venue to be done multiple times to obtain a dependable sample size that will provide
statistical significance (Utami, 2011).
2.5.2 Errors in EASE
An outline of quality of venue acoustic simulation tools through a comparative analysis of optimized test
scenarios and binaural measurements was created (Pelzer, Aretz, & Vorlander, 2011). EASE provides sufficient
simulation toward the visualization of the path of sound propagation from all the identified sources. There is a gap in
literature associated with the assessment of accuracy of the related algorithms based on the comprehensive
comparisons with the determined responses to impulses in a venue (Pelzer, Aretz, & Vorlander, 2011). Summers
indicates that the acoustic simulation software are prone to error, which is a factor that designers should consider
during the simulation process (Summers, 2003). Systematic errors in the predictions of acoustic software, when not
identified and addressed, can be caused by using seat absorption coefficients that emerge from the simulation
methods that are founded on diffuse-field presumptions (Summers, 2003).
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2.5.3 Reverberation time, (Boeck, Navvab, & Heilmann, 2012)
A case study on stadiums and theaters calculated reverberation times (Boeck, Navvab, & Heilmann, 2012).
The researchers used beamforming, which is an approach used in obtaining acoustic signatures of construction,
where it superimposes acoustic images using three-dimension models to establish similar maps that can be used in
designing places (Boeck, Navvab, & Heilmann, 2012). Citing the case of Michigan Stadium in the United States, the
authors cited the significance of measuring the reverberation time in building acoustics.
Through the use of the EASE software, reverberation time is calculated from the different parts of a venue.
Finding the mean of the results is statistically important in obtaining a reliable confidence level. When using three-
dimensional arrays, the reverberation time is calculated through determining the reverberation time of the individual
microphone arrays and finding their means (Boeck, Navvab, & Heilmann, 2012). Using this method heightens the
statistical confidence level even though the measurements of the different points of the venue are still important. The
resulting acoustic maps for the different reverberation times (RT) can, thus, be determined using carefully selected
integration durations, such fast, medium, and slow among others.
EASE software highlights reverberation time using the Sabine and Eyrling formulas for the associated
noise simulations. It further also enables the optimization of reverberation time, which enable fast predictions of the
effect brought by changing the acoustic material on the RT as well as the mean noise absorption coefficient through
the related frequencies. The other means through which the RT is optimized is the establishment of an RT curve
target and exploration of the available choices of acoustic material to attain the targeted RT curve. It is also done
through defining acoustic materials and allowing the EASE software to analyze and determine the best material that
matches the needed reverberation time or an absorption coefficient.
In their findings, the authors stated that the use of simulation software in the modelling of the theater’s
spaces and compartments facilitates the finding of the acoustic properties of any analyzed space. Although the
authors opted for the RAYNOISE software, it is important to note that some of the findings made using the model
can be created using the EASE software that this paper opts to use to conduct acoustic simulation in stadiums. The
emerging deviations created are of a low percentage, which in the case of the software used to simulate the
acoustics, it is less than 12 percent – a rate that is consistent with other geometrical methods applied in modelling of
compartments.
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2.6 Summary
As noise management is one of primary concerns of stadium managers, especially during matches and
music concerts, it is important that the designers obtain the most effective analytical tools for acoustic simulation.
Noise management has two main goals, one is to provide proper room acoustics, which controls the effective sound
production, transmission and perception of wanted sounds and accentuate them for listening. The other goal is to
provide noise control, which is to remove the unwanted noise coming from structure, mechanical equipment etc. that
can affect the user. Acoustic simulation software programs are useful in determining the effects of the sound
systems and the noise of match supporters as well as the manner through which the architectural designs of the
stadium and the construction materials can be used to minimize the effect of the noise that emanates from the
stadium. The review of related literature shows that there is a gap in research concerning the use of acoustic
simulations to understand the level of noise in stadiums. The review of the related studies and analysis as well as
reviews adds to the growing literature on acoustic simulation of sounds, particularly in stadiums.
The most effective way of achieving acceptable speech intelligibility is to use a distributed sound system
with no seat being more than about 80 feet from the nearest loudspeaker. Adding reflective surfaces will aid in
increasing reverberation in the stadiums. Longer reverberation times will pose speech intelligibility issues. The C80
value should not exceed +8 dB at any location. Sound systems should be designed to be at least 10 dBA louder than
the audience to be heard. Also, the sound pressure levels should not exceed 115 dBA for longer periods of time
which could pose a hearing issues to the audience. These valuable inputs were useful in streamlining the
methodology and analyzing the collected data while performing the design modification analysis of the Los Angeles
Memorial Coliseum, which is discussed in Chapter 6.
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Chapter 3: Methodology
3.1 Overview and demo model study
This chapter discusses the methodologies used for the acoustics study of the Harris Hall courtyard and the
Los Angeles Memorial Coliseum (Fig 3.1-1). Harris Hall courtyard at the University of Southern California was
chosen as a case study to analyze in a field study and then perform acoustic simulation using EASE. Concurrently a
Revit model and a Dynamo script was developed to perform the same. The Los Angeles Memorial Coliseum was
visited during the 2017 college football season to conduct acoustic measurement. Due to security reasons at the Los
Angeles Memorial Coliseum, an advanced Sound Pressure Level meter could not be taken inside during the football
games. Sound Analyzer app was installed on Google Pixel mobile device and used to collect data during the football
games. Acoustic conditions in Los Angeles Memorial Coliseum were simulated using EASE. Similarly, the Dynamo
script used for simulating the courtyard was modified to suit the stadium scenarios and the results are analyzed (this
was proposed, but not eventually done). Following the analysis of the results from the acoustic analysis,
modifications are made to the Coliseum, and the steps are repeated. The acoustic conditions are again simulated for
the Los Angeles Memorial Coliseum using EASE and the results are analyzed to draw conclusions on the acoustic
performance of the same.
Figure 3.1-1 An overview of the entire methodology
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Before developing a Dynamo script to simulate the acoustic conditions for the Revit model of both the case
studies, a small demo model was developed to calculate reverberation time of a room in Revit using Dynamo (Fig
3.1-2). The main concern being tested was if Dynamo would be a good choice for simulation. A shoe box model was
created in Revit. The formula for reverberation time is 𝑅𝑇 (60) = 0.05 𝑉 /(Ʃ𝑆𝛼 ) where RT(60) is the reverberation
time in seconds, V is the volume of the space in cubic feet, S is the surface area in square feet, α is the absorption
coefficient of material at a given frequency, Ʃ is the summation of S times the α for all surfaces (Egan, 1988).
Figure 3.1-2 A Dynamo script to calculate the reverberation time of a room
The first part of the script calculates the numerator which is 0.05V where V is the volume of the room (Fig
3.1-3). The space was modelled in Revit without any errors. The space was defined as a room using the room
bounding command in Revit. In order to calculate the volume of the room in Dynamo, the following parameters
were used in the script. Firstthe categories node was used to call out all elements in the particular category. “Rooms”
was chosen as the required category from the drop down list box. The “All elements of Category” node was used to
pull all the elements in the particular category. The “Room Area” and the “Room Height” nodes were used to pull
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out the respective values from the revit model and was multiplied to calculate the Volume of the room. By using this
method, it ensured that should there by any modifications to the revit model i.e change in the area of the room,
height etc. these nodes will change the output of the nodes respectively making it parametric.
Figure 3.1-3 Calculating the volume of the room
The next part of the script calculated the total absorption (ƩSα) (Fig 3.1-4). In order to calculate the total
absorption the area of the surface and their respective absorption coefficients (α) were required. The absorption
coefficients for the three different surfaces (wall, floor, and ceiling) were entered in separate code blocks. The wall,
ceiling and the surfaces were taken by using the “Select Face” node. The respective faces were selected, and the
“Surfacec Area” node was used to calculate the surface area. The nodes were grouped by the element types (Floor,
Wall and Ceiling). The summation of the surface area with the respective absorption coefficients is calculated by
using the “*” node. The results of the nodes are visualtized using the “Watch” node. Similar to the previous part of
the script, this segment is also parametric meaning any changes made in the model would reflect on the calculations
instantly making it easier to make any decision based on the final outcome.
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Figure 3.1-4 Calculating the overall absorption of the room
The final part of the script combines the two calculated values as per the equation (Fig 3.1-5). This segment
is also parametric meaning any changes made in the model would reflect on the calculations instantly making it
easier to make any decision based on the final outcome. The parametric ability of Dynamo makes it a very good
program to test out various options in terms of the design i.e materials, area, volume etc. to arrive at the best possible
solution. The results were consistent with doing the calculations by hand.
Figure 3.1-5 Calculating the reverberation time
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3.2 Harris Hall courtyard at University of Southern California
The Harris Hall courtyard at the University of Southern California was chosen as a case study (Fig. 3.2-1).
The space was chosen for its similarity to a stadium which is open to air with enclosures on four sides (Fig 3.2-2).
The courtyard was modelled in Revit and a Dynamo script was developed to run an acoustic simulation. The Harris
Hall courtyard space was exported as an AutoCAD 3d drawing and imported in Sketchup. Acoustic conditions were
simulated using acoustic software EASE. Dynamo script calculated the direct sound pressure level (SPL) at XY
plane of the model. The results from Dynamo script are validated using the results from EASE and the acoustic field
study.
Figure 3.2-1 Acoustic analysis of the Harris Hall courtyard at University of Southern California methodology overview
Figure 3.2-2 Harris Hall courtyard at University of Southern California
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3.2.1 Real time acoustic study at the Harris Hall courtyard at University of Southern California
Figure 3.2-3 Acoustic analysis of the Harris Hall courtyard at University of Southern California methodology
A real time acoustic analysis of the Harris Hall courtyard at University of Southern California was
performed on November 25
th
, 2017 during the Thanksgiving break. Mr. Neil Shaw from Menlo Acoustics offered to
help for conducting the acoustic field study at Harris Hall courtyard by providing acoustic measuring equipment.
The Yamaha Stagepas 400i speakers were procured for the study from the USC School of Architecture. The acoustic
data was collected using EASERA software. Test signals were generated using the EASERA application through the
Yamaha Stagepas speakers. The study was conducted using two different setups with the equipment. Results from
the study are described in section 4.2.1. Inferences from the study have been described in section 5.2. Additional
supporting data from the study are included in Appendix B: Supporting data from EASERA and the field study at
Harris Hall courtyard, University of Southern California.
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Figure 3.2-4 Harris Hall courtyard acoustic field study photographs
Setup-1
Setup-1 had the Yamaha Stagepas speakers placed in near the southern end of the Harris Hall courtyard facing
towards the northern side (Fig 3.2-2). The Audix TM-1 microphone was calibrated and placed 4 feet above ground
in the northern side. Audix TM-1 and Yamaha Stagepas 400i were connected with Rolland Octacapture which was
connected to the laptop to perform the study. Bruel & Kjaer type 2250 hand held analyzer was used to calibrate the
microphone for the study. EASERA program was set up to conduct a study with Audix TM-1, Rolland Octacapture
and Yamaha Stagepas 400i.
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Figure 3.2-5 Harris Hall acoustic study setup-1
Four different signal types (log sweep, MLS, pink noise, sweep) were played through the speakers using
EASERA program and the amplifier was set to the maximum volume. The signals were recorded through Audix
TM-1 and processed through EASERA software. The data collected from the study was saved in the EASERA as an
audio file format (.emd) file.
Setup-2
Setup-2 had the Yamaha Stagepas speakers placed in near the northern end of the Harris Hall courtyard facing
towards the southern side (Fig 3.2-3). The Audix TM-1 microphone was calibrated and placed 4 feet above ground
in the northern side. Audix TM-1 and Yamaha Stagepas 400i were connected with Rolland Octacapture which was
connected to the laptop to perform the study. Bruel & Kjaer type 2250 hand held analyzer was used to calibrate the
microphone for the study. EASERA program was set up to conduct a study with Audix TM-1, Rolland Octacapture
and Yamaha Stagepas 400i.
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Figure 3.2-6 Harris Hall acoustic study setup-2
Four different signal types (log sweep, MLS, pink noise, sweep) were played through the speakers using
EASERA program and the amplifier was set to the maximum volume. The signals were recorded through Audix
TM-1 and processed through EASERA software. The data collected from the study was saved in the EASERA as an
audio file format (.emd) file.
75
3.2.2 Revit & Dynamo
The Harris Hall courtyard space was then modeled in Revit and a Dynamo script was developed to simulate the
conditions of the acoustic field study. The results from the Dynamo script were validated by conducting simulations
using acoustic simulation software EASE.
Figure 3.2-7 Acoustic analysis of the Harris Hall courtyard at University of Southern California methodology
Algorithm of the Dynamo script
Based on the literature research, the algorithm to develop the Dynamo script was developed (Fig. 3.2-7).
Figure 3.2-8 Harris Hall courtyard Dynamo script methodology
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The Harris Hall courtyard was modeled in Revit. The materials and finishes were applied and made as
accurate as possible. An instant parameter was added to the material with the “absorption” values. Eight parameters
were added for every frequency in the one-third octa band (125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz,
8000 Hz). Measures were taken to keep the Revit model free of any errors.
The Dynamo script was divided into four parts: Revit data extraction, defining analysis grid and dividing
extracted surfaces into grids, defining the sound sources, and the ray trace analysis:
The first part extracted the surfaces and the material properties from the Revit model. All the extracted
surfaces (walls, floors, doors) are split into grids and made into a list in Dynamo. The output of these nodes showed
the surfaces in the Revit model on Dynamo workspace.
The second part of the script created a 3-dimensional grid over the entire model. The limits of the grids
were set in a way to make sure that the Revit model is fully inside the grid. The surfaces extracted in the previous
part were divided into grids to serve as the bounce off points during ray-trace function.
The third part of the script defined the point sound sources in the study. The Harris Hall courtyard acoustic
study had two sound sources. Each point source is defined by the following parameters. Sound pressure level (SPL)
based on one third octa band frequency (125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz, 8000 Hz), location
of the source as a point, direction of the sound source by defining a vector towards the target point from the source
point, number of bounces and the parameters to export the data as an Excel sheet.
The fourth part of the Dynamo script performed the ray trace analysis and the acoustic simulation in the
Revit model. The ray trace methodology used the principle of geometric acoustics (GA) where the rays are assumed
to carry sound energy and behave similar to light rays. Each point source projected a cone towards the direction
vector given in the node (Fig 3.2-9). Similarly, after refection from the surfaces, cones were projected towards the
normal vector direction of the incoming vector. The sound pressure levels were calculated on each point separately
in the 3-dimensional grid. A list was created for a point in the grid. The list had sound pressure levels as the inputs
after each bounce. For direct sound pressure level, the SPL at the point was directly calculated. When there were
multiple sources, the direct SPL is calculated by adding the SPL from all sources at the point. It should also be noted
that SPL levels decrease through distance. When a point source projects a cone, the SPL levels were added to the list
of SPL values to the points that fall within the volume of the cone. After the cone reached a wall or floor surface
where it is subject to reflection, the points in the wall act where the cone falls acted as starting points for the first
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bounce. Each point where the cone falls acted as the starting point with the respective vector based on the incoming
vector from the source location will be the direction vector for the next sequence.
Figure 3.2-9 Dynamo Script showing projection of cone from the point source locations during direct sound projection sequence
A cone was projected from the points on the wall or floor surfaces where the direct sound rays fell during
the first sequence of ray tracing towards the normal direction of the incoming rays. The list of points on which the
projected cones fall were filtered using the “Geometry.doesintersect” node. A test was created to check if the point
falls within the cone. True would return the sound pressure level at the point for this sequence and false returns zero.
When the ray reached the point on the floor or wall, the SPL level at the point was calculated. Before the start of
next sequence (bounce 1) the SPL level was again calculated, which would have reduced based on the absorption
coefficient (α) of the respective surface. The calculated SPL at the point after reflection or absorption becomes the
incident SPL for the next sequence. The same sequence followed based on the number of bounces given in the input.
Every time a point fell within the projected cone(s), the corresponding sound pressure level (SPL) at the point was
added to the list. After the completion of the full ray-trace sequence, each calculation point had several sound
pressure level (SPL) values, which were added to the list every time the point was inside the cone. The SPL values
were added together logarithmically, and the output was exported as an excel spreadsheet with the corresponding
coordinates.
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The above sequence is for calculation of the total SPL at a point for one frequency. The same process is
repeated for the other frequency values, and the output is exported as an Excel spreadsheet. The Dynamo script can
be found in Appendix H.
3.2.3 Acoustic software simulation – EASE
The Harris Hall courtyard was simulated using EASE to validate the results (Fig 3.2-10). The Revit model
used for Dynamo simulation was used as the primary model to convert to other formats for consistency in geometry.
The Revit model was exported as a DXF file and imported in Sketchup to simplify the model by removing surfaces
that won’t receive any reflections; this reduced the simulation run time.
Figure 3.2-10 Acoustic analysis of the Harris Hall courtyard at University of Southern California methodology
Enhanced Acoustic Simulator for Engineers (EASE) software was used to perform acoustic simulation for
courtyard. The Revit model of the courtyard was exported as a DXF file to save time. The .dwg file was then opened
in Sketchup to eliminate the unnecessary surfaces. All the surfaces that will not receive any reflections are
eliminated to expedite the computing process during simulations. The model was simplified to the minimum and
exported as a Sketchup8 file, which is an older version of the Sketchup software as EASE supports only up to
Sketchup 8 files for import (Fig 3.2-11).
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Figure 3.2-11 Harris Hall Courtyard Sketchup model images
The materials were applied in the Sketchup model that made it easier to apply materials on EASE (Table
3.2-1).
S.NO MATERIAL EASE MATERIAL NAME DESCRIPTION
1. Walls Generic, Brick, Unglazed,
Painted
Brick, unglazed, painted1 Octave Data: 125Hz-
4KHz Data from Sound System Engineering, 2
nd
Edition, pgs 158-159
2. Doors Generic, Door, Solid Core,
Wood
Door, 1 ¾” Solid core, wood,1 Octave Data:
125Hz-4KHz
3. Brick floor Generic, Brick, Unglazed Unglazed Bricks1 Octave Data: 125Hz-8KHz
Data from: Architectural Acoustics M David
Egan pg 52
4. Grass Generic, Grass, 2 inch thk Grass, Marion bluegrass 2" high 1 Octave Data:
125Hz-4KHz. Data from Architectural Acoustics
M David Egan pg 52
5. Window
Glazing
Generic, Glass, Window,
Plate, 0,25 inch thk, Heavy
Large Panes
Plate glass, Large Heavy Panes 1 Octave Data:
125Hz-4KHz Data From sound system
engineering, 2nd Edition, pgs 158-159
6. Concrete Generic, Concrete, Rough
Finish
Concrete wall or floor, Rough Finish 1 Octave
Data: 125Hz-4KHz Data Unattributed
Table 3.2-1 Harris Hall courtyard EASE model material list
The Sketchup model was purged to remove any unnecessary lines, objects and reduce the file size. The
model was exploded to sure that it becomes a single piece than several groups or components in Sketchup. After
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exploding the model, the “intersect faces” option was chosen to make sure that all the faces are connected to each
other. Failing to do this step would have resulted in finding holes in the model when imported into EASE.
A new project file is setup in EASE and the “Import CAD/DXF” option was used to import the Sketchup
model. EASE detects the materials applied on Sketchup model and provides an option to choose to apply any
material from EASE material database while importing. Similarly EASE also detects layers in a CAD drawing and
has an option to apply materials from EASE material database to each layer.
After importing the DXF/Sketchup model, the model was checked for any holes or errors using the “Check
holes” option in the “edit room” window. Any errors or holes were fixed in the model by using the “Close holes”
option in the “Check holes” window. Once the model was cleared of errors, speaker systems were placed in the
model. EASE has an extensive speaker database that can be accessed through the “Place speaker” option.
Speakers can be placed individually or as an array depending on the need. EASE also provides option to
place lights in the model through its “Light database”. Speakers are grouped so that they can be turned on or off
while running simulations. EASE has an option to look from the POV (Point of View) of the element while placing
them in the model. This will help in aiming the speaker towards the intended target. EASE has an “Listener’s seat”
option that will calculate acoustic parameters in the particular location in addition to the sound mapping from the
simulations. The “Listener’s seats” are placed on the locations where data was collected during the acoustic field
study, but for the courtyard EASE’s option to define “Audience area” in the model was used. Audience area is
defined by drawing a rectangle over the courtyard space. All the mapping calculations will be performed at the
“audience areas” defined in the model (Fig 3.2-6). Two setups were used to collect data from the acoustic field study
at the Harris Hall courtyard. The placement of “Listener seats” and “Speakers” were placed as per the field study
measurements. Both the setups were grouped under their respective names which will make it easier to choose
during mapping simulations.
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Figure 3.2-12 Harris Hall courtyard EASE model
After defining the audience area, the model was inspected for any missing elements. Check data option was
run to find any errors in the model and it was rectified. The “Compute data” option was run for EASE to analyze the
model. The model was checked again for holes or errors. After fixing errors, the “Edit Room” window was closed,
and the “Mapping” module was loaded in EASE.
The “Mapping” module contains 2D mapping of direct SPL and total SPL, 3D mapping of direct SPL and
total SPL, rendered view of the model, C7 mapping, C50 mapping, C80 mapping, L7 mapping, L50 mapping, L80
mapping. Each of the functions runs as a separate simulation while loaded, and the results are shown as mapping
with a color scale. All the mapping renders were exported as an image. The results from the EASE simulation of the
Harris Hall courtyard have been described in section 4.2.3Error! Reference source not found.. Additional s
upporting data that could not be included in these results are described in Appendix B.
.
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3.3 Los Angeles Memorial Coliseum
The Los Angeles Memorial Coliseum serves as the home to the University of Southern California college
football team (USC Trojans) and the temporary home to the Los Angeles Rams of the National Football League
(NFL). An acoustic field study was conducted during the college football season of USC Trojans (Fig 3.3-1). The
stadium has a seating capacity of 93,607 for the football games (Fig 3.3-2). The Coliseum has also hosted the
summer Olympics twice in 1932 and 1984 (Los Angeles Memorial Coliseum, 2017). Similarly, the Los Angeles
Memorial Coliseum was simulated using EASE to analyze the acoustic performance. Based on the observations
from the simulation and field studies two design modifications were proposed. The results from the study are
explained in section 4.3. The observations and inferences from the study are explained in section 5.3.
Figure 3.3-1 Acoustic field study at the Los Angeles Memorial Coliseum methodology
Figure 3.3-2 Los Angeles Memorial Coliseum during the college football game
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Based on the observations and interpretations from EASE simulation results and field study of the
Coliseum, two design modifications were proposed, and the design modification analysis of the Los Angeles
Memorial Coliseum is described in chapter 6. The Coliseum is currently under renovation with the construction
work set to take over 2 periods of 8 months with the 2018 college football season in between (Los Angeles
Memorial Coliseum, 2017). The renovation project is expected to be completed by the start of 2019 football season
(Los Angeles Memorial Coliseum, 2017). The seating capacity will be reduced from 93,607 to 77,500 (Los Angeles
Memorial Coliseum, 2017). One of the proposed design options in the design modification analysis of the Coliseum
will be the newly proposed renovation, which is described in chapter 6.
3.3.1 Real time acoustic analysis of the Los Angeles Memorial Coliseum during the 2017-18 college
football season
Los Angeles Memorial Coliseum was visited during the 2017-18 college football season (Fig 3.3-3). USC
Trojans played 7 home games at the Coliseum (Table 3.3-1).
Figure 3.3-3 Acoustic field study at the Los Angeles Memorial Coliseum methodology
The Extech HD 600 and Sound Analyzer app was used to record data during the football game. Due to
security reasons, advanced sound pressure level meters could not be taken inside the stadium during game play.
Sound Analyzer app was installed on the mobile device and calibrated using Extech HD 600 before collecting data
in the Coliseum.
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S.No Date Start
of play (PT)
Opponent Home/Away Final
score
Attendance
1. 09/02/2017 02:15 PM Western Michigan Home 49-31 61125
2. 09/09/2017 05:30 PM Stanford Cardinals Home 42-24 77614
3. 09/16/2017 05:30 PM Texas Longhorns Home 27-24 84714
4. 09/23/2017 12:30 PM California Golden Bears Away 30-20 46747
5. 09/29/2017 07:30 PM Washington State Away 27-30 33773
6. 10/07/2017 01:00 PM Oregon State Beavers Home 38-10 60314
7. 10/14/2017 05:00 PM Utah Utes Home 28-27 72382
8. 10/21/2017 04:30 PM Notre Dame Away 14-49 77622
9. 01/28/2017 07:45 PM Arizona State Away 48-17 53446
10. 11/04/2017 07:45 PM Arizona Wildcats Home 49-35 70225
11. 11/11/2017 01:00 PM Colorado Away 38-24 49337
12. 11/18/2017 05:00 PM UCLA Bruins Home 28-23 82407
Table 3.3-1 USC Trojans college football 2017-18 season schedule and results (University of Southern California Athletics,
2018)
Data was recorded using Sound Analyzer app in the mobile device. The first quarter of the game was spent
in the student section to record data. During the second and third quarters, the alumni/public stands and the visiting
fans stands were visited to collect data (Fig 3.3-4). Recorded data was exported as an Excel worksheet (.xlsx format)
with time stamp. Concurrently observations were made during the game to look for audience response during the
game. The results from the study are explained in section 4.3.1.
Figure 3.3-4 Seating chart of the Los Angeles memorial coliseum (Los Angeles Memorial Coliseum, 2017)
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3.3.2 Revit & Dynamo
A 3d model of the Los Angeles Memorial Coliseum was developed in Revit to be used for developing the
Dynamo script (Fig 3.3-5). The Dynamo script developed for the Harris Hall courtyard was modified to suit stadium
conditions, and the results would have been exported as images and Excel spreadsheets except for the failure of the
script when developing to simulate acoustic conditions.
Figure 3.3-5 Acoustic field study at the Los Angeles Memorial Coliseum methodology
3.3.3 Acoustic software simulation – EASE
Enhanced Acoustic Simulator for Engineers (EASE) software was used to perform acoustic simulation for
the Los Angeles Memorial Coliseum. (Fig 3.3-6).
Figure 3.3-6 Acoustic field study at the Los Angeles Memorial Coliseum methodology
EASE supports importing geometry from DXF and SKP (Sketchup) formats. The Revit model of the
Coliseum had more surfaces which would have taken longer for computation. Hence a simplified model of the
Coliseum was made in AutoCAD and was exported as a DXF file (Fig 3.3-7). The curvilinear surfaces were
simplified into planar polygons to reduce the complexity of the geometry and reduce simulation times. The DXF file
was then opened in Sketchup to eliminate the unnecessary surfaces. All the surfaces that did not receive any
86
reflections were eliminated to expedite the computing process during simulations. The model was simplified to the
minimum and exported as a Sketchup8 file which is the format supported by EASE.
Figure 3.3-7 Los Angeles Memorial Coliseum AutoCAD 3d model
The materials were applied on the Sketchup model as that made it easier to apply materials on EASE. The
Sketchup model was purged to remove any unnecessary lines, objects, and reduce the file size. The model was
exploded to sure that it becomes a single piece than several groups or components in Sketchup. After exploding the
model, the “intersect faces” option was chosen to make sure that all the faces are connected to each other. Failing to
perform this step will result in finding holes in the model when imported into EASE.
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Figure 3.3-8 Los Angeles Memorial Coliseum Sketchup model
A new project file is setup in EASE and the “Import CAD/DXF” option was used to import the Sketchup
model. EASE detects the materials applied on Sketchup model and provides an option to choose to apply any
material from EASE material database while importing (Table 3.3-2). Similarly EASE also detects layers in a CAD
drawing and has an option to apply materials from EASE material database to each layer.
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S.NO MATERIAL EASE MATERIAL NAME DESCRIPTION
1. Walls Generic, Brick, Unglazed,
Painted
Brick, unglazed, painted1 Octave Data: 125Hz-
4KHz Data from Sound System Engineering, 2
nd
Edition, pgs 158-159
2. Brick floor Generic, Brick, Unglazed Unglazed Bricks1 Octave Data: 125Hz-8KHz
Data from: Architectural Acoustics M David
Egan pg 52
3. Grass Generic, Grass, 2 inch thk Grass, Marion bluegrass 2" high 1 Octave Data:
125Hz-4KHz. Data from Architectural Acoustics
M David Egan pg 52
4. Glazing over
press box
Generic, Glass, Window,
Plate, 0,25 inch thk, Heavy
Large Panes
Plate glass, Large Heavy Panes 1 Octave Data:
125Hz-4KHz Data From sound system
engineering, 2nd Edition, pgs 158-159
5. Concrete Generic, Concrete, Rough
Finish
Concrete wall or floor, Rough Finish 1 Octave
Data: 125Hz-4KHz Data Unattributed
6. Audience
stands
Generic, People, in Fully
Covered Seats, per Person
People in fully covered seats per person
1 Octave Data: 125Hz-4KHz
Data From Audio System Designer Technical
Handbook
Table 3.3-2 Los Angeles Memorial Coliseum EASE material list
After importing the DXF/Sketchup model, the model was checked for any holes or errors using the “Check
holes” option in the “edit room” window. Any errors or holes are fixed in the model by using the “Close holes”
option in the “Check holes” window. Once the model was cleared of errors, speaker systems were placed in the
model. EASE has an extensive speaker database which can be accessed through the “Place speaker” option.
Speakers can be placed individually or as an array depending on the need. EASE also provides option to place lights
in the model through its “Light database”. Speakers are grouped so that they can be turned on or off while running
simulations. EASE has an option to look from the POV (Point of View) of the element while placing them in the
model. This will help in aiming the speaker arrays towards the intended target. EASE has an “Listener’s seat” option
which will calculate acoustic parameters in the location in addition to the sound mapping from the simulations. The
“Listener’s seats” were placed on the locations where data was collected during the football games. EASE provides
an option to define “Audience area” in the model which was helpful while conducting simulations for large spaces.
The audience area was defined by drawing a quadrilateral over the stands in the model (Fig 3.3-9).
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Figure 3.3-9 Los Angeles Memorial Coliseum EASE model
After defining the audience area, the model was inspected for any missing elements. Check data option was
run to find any errors in the model and it was rectified. The “Compute data” option was run for EASE to analyze the
model. The model was checked again for holes or errors. After fixing errors, the “Edit Room” window was closed,
and the “Aura” module was loaded in EASE.
Mapping module contains 2D mapping, 3D mapping, rendered view of the model, C7 mapping, C50
mapping, first arrival time mapping, loudspeaker overlaps mapping. Each of the functions run as a separate
simulation while loaded and the results are showed as mapping with a color scale. All the mapping renders were
exported as an image. The results are also shown as tables and graphs based on the frequency range that can be
exported as an Excel spreadsheet. The results from the EASE simulation of the Los Angeles Memorial Coliseum are
described in section 4.3.3. Additional supporting data that could not be reported in results are described in Appendix
D: Additional data from EASE simulation of Los Angeles Memorial Coliseum.
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3.4 Summary
Chapter 3 explained the research methodology used for the study. The Los Angeles Memorial Coliseum was
chosen to study stadium acoustics. The Harris Hall courtyard at University of Southern California was chosen for its
similar spatial configuration and smaller scale as a case study to analyze exterior acoustics and develop the tool to
simulate acoustics. A Revit model of the space was made, and a Dynamo script was developed to simulate the
acoustics. The tool was later developed to simulate the acoustics in a stadium environment. Similarly, a Revit model
of the Coliseum was made, and the Dynamo script was modified to suit the stadium acoustics. The results from
Dynamo were validate using acoustic simulation software EASE. The results from the studies are described in
Chapter 4 under section 4.2 for the Harris Hall courtyard and 4.3 for the Los Angeles Memorial Coliseum.
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Chapter 4: Results
4.1 Overview and the updated methodology
This section will examine the results obtained from the field study and acoustic software simulations. The
previous chapter described the methodology. After the development of the Dynamo script for running the acoustic
simulation on Revit models, the script crashed due to the instability of the software, which could not handle the
complex calculations associated with the ray tracing algorithm. The results turned out to be suspiciously similar to
each other even after trying several methods of simplifying the script to perform the same set of calculations. It was
concluded that the current version of Dynamo cannot handle the complexity of the script. Therefore, the
methodology was updated to focus on the acoustic simulation analysis of the Los Angeles Memorial Coliseum and
come up with two design options which could provide a better overall acoustic experience. The updated
methodology diagram was updated to show the focus of the acoustic study of the courtyard and stadium and possible
renovations. (Fig 4.1-1).
Figure 4.1-1 Updated methodology diagram focusing on the acoustic analysis of the study spaces
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4.2 Harris Hall courtyard at the University of Southern California
The acoustic field study at the Harris Hall courtyard of the University of Southern California was
conducted to collect acoustic data that can be used as a benchmark for the Dynamo script results and the acoustic
simulation results. This section will show the results obtained from three different sources for the Harris Hall
courtyard (EASERA, EASE).
4.2.1 Real time acoustic study results of Harris Hall courtyard at the University of Southern California
The following are the results obtained from the EASERA software during the acoustic field study
conducted at the Harris Hall courtyard at the University of Southern California (Fig 4.2-1). The setup for the study
included Audix TM-1, Rolland OCTACAPTURE and the Yamaha Stagepas 400i connected to perform the various
acoustic testing. The Bruel and Kjaer type 2250 hand-held analyzer was used to calibrate the test microphone for the
study.
Figure 4.2-1 Harris Hall courtyard methodology overview
EASERA was used to generate four types of test signals namely Log sweep, MLS (Maximum Length
Sequence) signal, Pink noise and Sweep noise. Two configurations of the equipment were setup and the four signal
tests were performed at each location. EASERA recorded the signals during each test and provided the impulse
response graphs, 3d waterfall graphs, clarity measurements (C7, C50, C80), arrival time, EDT (Early Decay Time),
articulation loss of consonants (Al cons), speech transmission index (STI, RaSTI) for each case (Fig 4.2-2).
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Figure 4.2-2 Harris Hall courtyard acoustic field study results overview
Recommended values for the acoustic parameters calculated in the field study using EASERA
The following sections will describe the results calculated from the field study and EASE simulations of the Harris
Hall courtyard. The significance and the recommended values of each of the acoustic parameters are explained as
follows:
Impulse response graph
The impulse response is plotted in decibels (dB) along Y-axis with the frequency plotted in X-axis. It helps
in finding similar reflections and sound impulse patterns at the measuring location which will help in identifying any
acoustic defects such as late reflections, flutter echoes and deciding on treatment. Early reflections can be identified
by looking for similar patterns with reduced energy.
3d waterfall graph
The 3d waterfall graph will help find the dominant frequency range of the recorded signal and their
reflections off the timeline, which could help in designing the acoustics.
Speech Transmission Index
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
94
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009).
Articulation loss of consonants
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable.
Clarity measurements
Clarity in acoustics is a parameter to evaluate the degree of separation of successive sounds. It is a ratio of
the early sound to the reverberant sound after a certain amount of time (ADA (Acoustic Design Anhert), 2009). C7
is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct sound field
(ADA (Acoustic Design Anhert), 2009). C50 measures the speech clarity which is the ratio between the early and
late reflections in a space after 50 ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are
considered good (ADA (Acoustic Design Anhert), 2009). Values above – 5 dB are considered good for spaces with
higher reverberation (ADA (Acoustic Design Anhert), 2009). C80 is ratio of direct and late reflections after 80ms
(ADA (Acoustic Design Anhert), 2009). It is used for evaluating the musical clarity of a space. The C80 value
should not exceed +8 dB at any location.
Measurement of clarity based on frequency ranges will aid in understanding the behavior of various types
of sources. Clarity measurements play a major role while designing for musical instruments. Each type of instrument
will produce sound within a frequency range and recommended clarity values.
Setup-1
The setup-1 had the Yamaha Stagepas 400i facing northern direction of the courtyard. The acoustic tests
were conducted to collect data on the Audix TM-1 for four types of signals namely Log sweep, MLS, Pink noise and
Sweep noise.
Log sweep signal test
The first test to be conducted was the Log sweep signal test. The results from the test were saved as an
audio (.emd) file, which can be opened using EASERA program. EASERA program analyzed the data from the
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audio signal and provided results as graphs and tables. The following are the results from the Log sweep signal test
of setup-1 at Harris Hall courtyard.
The Impulse Response graph of the Log sweep test for setup-1 for Harris Hall is a 2-dimensional graph
where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted along Y-
axis in mPa (millipascal) (Fig 4.2-3). The impulse response is plotted in decibels (dB) along Y-axis with the
frequency plotted in X-axis. It helps in finding similar reflections and sound impulse patterns at the measuring
location which will help in identifying any acoustic defects such as late reflections, flutter echoes and deciding on
treatment. Early reflections can be identified by looking for similar patterns with reduced energy.
Figure 4.2-3 Harris Hall courtyard setup-1 Log sweep Impulse response
The Echogram graph of the Log sweep signal test for setup-1 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in dB (decibels) (Fig 4.2-4). The impulse response is plotted in decibels (dB) along Y-axis. Time
between successive reflections can be measured by analyzing the impulse response graph. It helps in finding similar
reflections and sound patterns at the measuring location which will help in identifying any acoustic defects such as
late reflections, flutter echoes and deciding on acoustic treatment.
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Figure 4.2-4 Harris Hall courtyard setup-1 Log sweep Echogram (Full IR)
The 3d waterfall graph of the Log sweep signal test for setup-1 is a 3-dimensional isometric graph with the
frequencies plotted along X-axis in Hz (hertz), time is plotted along Y-axis in microseconds and the corresponding
sound pressure level is plotted along Z-axis in dB (decibels) (Fig 4.2-5). The 3d waterfall graph will help find the
dominant frequency range of the recorded signal and their reflections off the timeline, which could help in designing
the acoustics.
Figure 4.2-5 Harris Hall courtyard setup-1 Log sweep 3D waterfall graph
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The following results were calculated by EASERA program form the data that was collected during the
acoustic field study at the courtyard. EASERA calculated the speech transmission index (STI), AL cons (Articulation
Loss of Consonants), speech transmission index (STI) male, speech transmission index (STI) female (Table 4.2-1).
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered excellent
(dark green in table). 0.6 to 0.75 is considered good (light green in table). 0.45 to 0.6 is considered fair (yellow in
table). 0.3 to 0.45 is considered poor (red in table). STI values below 0.3 are unacceptable (dark red in table) (ADA
(Acoustic Design Anhert), 2009).
STI 0.679
AlCons % 4.292
STI (Male) 0.698
STI (Female) 0.711
RaSTI 0.646
Equiv. STIPa (Male) 0.711
Equiv. STIPa (Female) 0.722
Table 4.2-1 Harris Hall courtyard setup-1 log sweep STI, AlCons, RaSTI
The Clarity measures of the Log sweep signal for setup-1 of the courtyard study at was calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are calculated as per the frequency by EASERA
(Table 4.2-2). Values shaded in green are acceptable values. Clarity in acoustics is a parameter to evaluate the
degree of separation of successive sounds. It is a ratio of the early sound to the reverberant sound after a certain
amount of time (ADA (Acoustic Design Anhert), 2009). C7 is ratio of direct and reverberant sound after 7 ms. It can
be used to analyze the strength of the direct sound field (ADA (Acoustic Design Anhert), 2009). C50 measures the
speech clarity which is the ratio between the early and late reflections in a space after 50 ms (ADA (Acoustic Design
Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic Design Anhert), 2009).
Values above – 5 dB are considered good for spaces with higher reverberation (ADA (Acoustic Design Anhert),
2009). C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space. The C80 value should not exceed +8 dB at any location.
98
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
250Hz-
2kHz
500Hz-
4kHz
dB dB dB dB dB dB dB dB dB
C7 (1/1
Oct.)
-
19.4 -9.1
-
15.5 -1.7 -4 -0.6 2.5 -7.6 -5.4
C50 (1/1
Oct.) -1.9 2.4 1.9 6.7 6.5 7.8 13 4.4 5.7
C80 (1/1
Oct.) 2.1 5.2 3.4 8.2 7.9 9.9 16.5 6.2 7.3
Csplit (1/1
Oct.) -3.2 -3.3 0.1 4.8 4.5 5.4 9.7 1.6 3.7
Table 4.2-2 Harris Hall courtyard setup-1 Log sweep Clarity measures
The Clarity measures of the Log sweep signal for setup-1 of the courtyard study was calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are plotted in the graph with the frequency along
X- axis in KHz, sound pressure in decibels (dB) along Y-axis (Fig 4.2-6). Measurement of clarity based on
frequency ranges will aid in understanding the behavior of various types of sources. Clarity measurements play a
major role while designing for musical instruments. Each type of instrument will produce sound within a frequency
range and recommended clarity values.
Figure 4.2-6 Harris Hall courtyard setup-1 Log sweep C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80, Grey –
Csplit)
The overall results for the Log sweep signal test for setup-1 at Harris Hall courtyard at are calculated in
EASERA (Table 4.2-3). The results are specific to the data collection point for this signal test. Speech
Transmission Index measures the quality of speech transferred from speaker to listener (ADA (Acoustic Design
99
Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered excellent. 0.6 to 0.75 is
considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values below 0.3 are unacceptable
(ADA (Acoustic Design Anhert), 2009).
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable.
Ln is the noise level exceeded for n% of the measurement time. “n” is a percentile value that can vary from
1 to 99 (Castle Group Ltd, 2018). Advanced sound pressure level meters can measure sound in percentiles. Each
percentile values helps in analyzing the noise levels. Values in white cannot be classified as good or bad values as
they are relative to the acoustic setting and they help us in understanding the overall acoustic performance at the data
collection point.
Setup-1 Log sweep impulse response
C7 dB -3.8
C50 dB 3.8
C80 dB 6.3
C35 dB 2.2
D 0.706
L7 dB SPL 72.5
L50 dB SPL 76.3
L80 dB SPL 76.9
L35 dB SPL 75.8
Ltotal dB SPL 77.8
Center time ms 58.91
ST1 dB 0.7
ST2 dB 1.7
Arrival Time ms 62.92
Split Time ms 35
EDT s 1.33
T10 s 1.72
T20 s 1.66
T30 s 1.72
Table 4.2-3 Harris Hall courtyard setup-1 Log sweep results
MLS signal test
The next test to be conducted was the MLS signal test. The results from the test were saved as an audio
(.emd) file that can be opened using EASERA program. EASERA program analyzed the data from the audio signal
100
and provided results as graphs and tables. The following are the results from the MLS signal test of setup-1 at Harris
Hall courtyard.
The Impulse Response graph of the MLS test for setup-1 at Harris Hall courtyard is a 2-dimensional graph
where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted along Y-
axis in mPa (millipascal) (Fig 4.2-7). The impulse response is plotted in decibels (dB) along Y-axis. It helps in
finding similar reflections and sound impulse patterns at the measuring location which will help in identifying any
acoustic defects such as late reflections, flutter echoes and deciding on treatment. Early reflections can be identified
by looking for similar patterns with reduced energy.
Figure 4.2-7 Harris Hall courtyard setup-1 MLS Impulse response
The Echogram graph of the MLS signal test for setup-1 at Harris Hall courtyard is a 2-dimensional graph
where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted along Y-
axis in dB (decibels) (Fig 4.2-8). The impulse response is plotted in decibels (dB) along Y-axis. Time between
successive reflections can be measured by analyzing the impulse response graph. It helps in finding similar
reflections and sound patterns at the measuring location which will help in identifying any acoustic defects such as
late reflections, flutter echoes and deciding on acoustic treatment. The spike in the graph shows the start of the next
cycle of the signal.
101
Figure 4.2-8 Harris Hall courtyard setup-1 MLS Echogram (Full IR)
The 3D waterfall graph of the MLS signal test for setup-1 at Harris Hall courtyard is a 3-dimensional
isometric graph with the frequencies plotted along X-axis in Hz (hertz), time is plotted along Y-axis in microseconds
and the corresponding sound pressure level is plotted along Z-axis in dB (decibels) (Fig 4.2-9). The graph will help
find the dominant frequency range of the recorded signal and their reflections off the timeline which could help in
designing the acoustics.
Figure 4.2-9 Harris Hall courtyard setup-1 MLS 3D waterfall graph
The following results were calculated by EASERA program form the data that was collected during the
acoustic field study at Harris Hall courtyard. EASERA calculated the speech transmission index (STI), AL cons
(Articulation Loss of Consonants), speech transmission index (STI) male, speech transmission index (STI) female
(Table 4.2-4).
102
STI 0.625
AlCons % 5.780
STI (Male) 0.642
STI (Female) 0.649
RaSTI 0.605
Equiv. STIPa (Male) 0.657
Equiv. STIPa (Female) 0.662
Table 4.2-4 Harris Hall courtyard setup-1 MLS signal STI, AlCons, RaSTI
The Clarity measures of the MLS signal for setup-1 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are plotted in the graph with the frequency along
X- axis in KHz, sound pressure in decibels (dB) along Y-axis (Fig 4.2-10).
Figure 4.2-10 Harris Hall courtyard setup-1 MLS C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80, Grey – Csplit)
The Clarity measures of the MLS signal for setup-1 of Harris Hall courtyard study was calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are calculated as per the frequency by EASERA
(Table 4.2-5). Measurement of clarity based on frequency ranges will aid in understanding the behavior of various
types of sources. Clarity measurements play a major role while designing for musical instruments. Each type of
instrument will produce sound within a frequency range and recommended clarity values.
103
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
250Hz-
2kHz 500Hz-4kHz
dB dB dB dB dB dB dB dB dB
C7 (1/1
Oct.) -19.5 -9.1 -15.4 -2.6 -4.3 -4.1 1 -7.9 -6.6
C50 (1/1
Oct.) -2.2 2.1 1.1 5.9 4.7 5.8 7.4 3.4 4.4
C80 (1/1
Oct.) 1.6 4.5 3 7.1 6.4 7.3 8.4 5.2 5.9
Csplit (1/1
Oct.) -3 -3.3 -0.3 4.7 2.7 3.8 5.9 0.9 2.7
Table 4.2-5 Harris Hall courtyard setup-1 MLS Clarity measures
The overall results for the MLS signal test for setup-1 at Harris Hall courtyard were calculated in
EASERA. The results are specific to the data collection point for this signal test (Table 4.2-6).
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009).
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable.
Ln is the noise level exceeded for n% of the measurement time. “n” is a percentile value that can vary from
1 to 99 (Castle Group Ltd, 2018). Advanced sound pressure level meters can measure sound in percentiles. Each
percentile values helps in analyzing the noise levels. Values in white cannot be classified as good or bad values as
they are relative to the acoustic setting and they help us in understanding the overall acoustic performance at the data
collection point. Values in white cannot be classified as good or bad values as they are relative to the acoustic setting
and they help us in understanding the overall acoustic performance at the data collection point.
104
Setup-1 MLS impulse response
C7 dB -6.0
C50 dB 2.1
C80 dB 4.6
C35 dB 0.8
D 0.619
L7 dB SPL 73.6
L50 dB SPL 78.5
L80 dB SPL 79.2
L35 dB SPL 77.9
Ltotal dB SPL 80.6
Center time ms 136.48
ST1 dB 2.3
ST2 dB 3.4
Arrival Time ms 63.10
Split Time ms 35
EDT s 1.45
T10 s 1.91
T20 s 1.76
T30 s 2.06
Table 4.2-6 Harris Hall courtyard setup-1 MLS results
Pink noise test
The next test to be conducted was the Pink noise signal test. The results from the test were saves as an
audio (.emd) file which can be opened using EASERA program. EASERA program analyzed the data from the
audio signal and provided results as graphs and tables. The following are the results from the Pink noise signal test
of setup-1 at Harris Hall courtyard.
The Impulse Response graph of the Pink noise test for setup-1 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in mPa (millipascal) (Fig 4.2-11).
105
Figure 4.2-11 Harris Hall courtyard setup-1 Pink noise Impulse response
The Echogram graph of the Pink noise signal test for setup-1 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in dB (decibels) (Fig 4.2-12).
Figure 4.2-12 Harris Hall courtyard setup-1 Pink noise Echogram (Full IR)
The 3D waterfall graph of the Pink noise signal test for setup-1 at Harris Hall courtyard is a 3-dimensional
isometric graph with the frequencies plotted along X-axis in Hz (hertz), time is plotted along Y-axis in microseconds
and the corresponding sound pressure level is plotted along Z-axis in dB (decibels) (Fig 4.2-13).
106
Figure 4.2-13 Harris Hall courtyard setup-1 Pink noise 3D waterfall graph
The following results were calculated by EASERA program form the data that was collected during the
acoustic field study. EASERA calculated the sound transmission index (STI), AL cons (Articulation Loss of
Consonants), speech transmission index (STI) male, speech transmission index (STI) female (Table 4.2-7). Clarity
in acoustics is a parameter to evaluate the degree of separation of successive sounds. It is a ratio of the early sound
to the reverberant sound after a certain amount of time (ADA (Acoustic Design Anhert), 2009). C7 is ratio of direct
and reverberant sound after 7 ms. It can be used to analyze the strength of the direct sound field (ADA (Acoustic
Design Anhert), 2009). C50 measures the speech clarity which is the ratio between the early and late reflections in a
space after 50 ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good
(ADA (Acoustic Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher
reverberation (ADA (Acoustic Design Anhert), 2009). C80 is ratio of direct and late reflections after 80ms (ADA
(Acoustic Design Anhert), 2009). It is used for evaluating the musical clarity of a space. The C80 value should not
exceed +8 dB at any location.
107
STI 0.620
AlCons % 5.926
STI (Male) 0.634
STI (Female) 0.640
RaSTI 0.601
Equiv. STIPa (Male) 0.644
Equiv. STIPa (Female) 0.646
Table 4.2-7 Harris Hall courtyard setup-1 Pink noise signal STI, AlCons, RaSTI
The Clarity measures of the Pink noise signal for setup-1 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are plotted in the graph with the frequency along
X- axis in KHz, sound pressure in decibels (dB) along Y-axis (Fig 4.2-14). Measurement of clarity based on
frequency ranges will aid in understanding the behavior of various types of sources. Clarity measurements play a
major role while designing for musical instruments. Each type of instrument will produce sound within a frequency
range and recommended clarity values.
Figure 4.2-14 Harris Hall courtyard setup-1 Pink noise C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80, Grey –
Csplit)
The Clarity measures of the Pink noise signal for setup-1 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are calculated as per the frequency by EASERA
(Table 4.2-8). Clarity in acoustics is a parameter to evaluate the degree of separation of successive sounds. It is a
ratio of the early sound to the reverberant sound after a certain amount of time (ADA (Acoustic Design Anhert),
2009). C7 is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct
sound field (ADA (Acoustic Design Anhert), 2009). C50 measures the speech clarity which is the ratio between the
108
early and late reflections in a space after 50 ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a
space are considered good (ADA (Acoustic Design Anhert), 2009). Values above – 5 dB are considered good for
spaces with higher reverberation (ADA (Acoustic Design Anhert), 2009). C80 is ratio of direct and late reflections
after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for evaluating the musical clarity of a space. The C80
value should not exceed +8 dB at any location.
125 Hz 250 Hz 500 Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
250Hz-
2kHz
500Hz-
4kHz
dB dB dB dB dB dB dB dB dB
C7 (1/1 Oct.) -19.4 -9.7 -14.3 -1.7 -2.5 -0.6 -3.8 -7.1 -4.8
C50 (1/1 Oct.) -2 1.9 1.1 5.5 5.1 5.5 6 3.4 4.3
C80 (1/1 Oct.) 2.1 4.6 2.8 6.6 6.2 6.8 7.9 5.1 5.6
Csplit (1/1
Oct.) -3 -3.4 -0.3 4.1 3.4 3.7 3.8 0.9 2.7
Table 4.2-8 Harris Hall courtyard setup-1 Pink noise Clarity measures
The overall results for the Pink noise signal test for setup-1 at Harris Hall courtyard are calculated in
EASERA. The results are specific to the data collection point for this signal test (Table 4.2-9).
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009).
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable.
Ln is the noise level exceeded for n% of the measurement time. “n” is a percentile value that can vary from
1 to 99 (Castle Group Ltd, 2018). Advanced sound pressure level meters can measure sound in percentiles. Each
percentile values helps in analyzing the noise levels. Values in white cannot be classified as good or bad values as
they are relative to the acoustic setting and they help us in understanding the overall acoustic performance at the data
collection point.
109
Setup-1 Pink noise impulse response
C7 dB -4.5
C50 dB 2.7
C80 dB 5.1
C35 dB 1.2
D 0.649
L7 dB SPL 83.4
L50 dB SPL 87.3
L80 dB SPL 88.0
L35 dB SPL 86.8
Ltotal dB SPL 89.2
Center time ms 123.44
ST1 dB 0.8
ST2 dB 1.9
Arrival Time ms 63.06
Split Time ms 35
EDT s 1.34
T10 s 1.76
T20 s 1.68
T30 s 1.63
Table 4.2-9 Harris Hall courtyard setup-1 Pink noise results
Sweep noise test
The next test to be conducted was the Sweep noise signal test. The results from the test were saves as an
audio (.emd) file which can be opened using EASERA program. EASERA program analyzed the data from the
audio signal and provided results as graphs and tables. The following are the results from the Sweep noise signal test
of setup-1 at Harris Hall courtyard.
The Impulse Response graph of the Sweep noise test for setup-1 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in mPa (millipascal) (Fig 4.2-15). The impulse response is plotted in decibels (dB) along Y-axis. It
helps in finding similar reflections and sound impulse patterns at the measuring location which will help in
identifying any acoustic defects such as late reflections, flutter echoes and deciding on treatment. Early reflections
can be identified by looking for similar patterns with reduced energy.
110
Figure 4.2-15 Harris Hall courtyard setup-1 Sweep noise Impulse response
The Echogram graph of the Sweep noise signal test for setup-1 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in dB (decibels) (Fig 4.2-16). The impulse response is plotted in decibels (dB) along Y-axis. Time
between successive reflections can be measured by analyzing the impulse response graph. It helps in finding similar
reflections and sound patterns at the measuring location that will help in identifying any acoustic defects such as late
reflections and flutter echoes and deciding on acoustic treatment.
Figure 4.2-16 Harris Hall courtyard setup-1 Sweep noise Echogram (Full IR)
The 3D waterfall graph of the Sweep noise signal test for setup-1 at Harris Hall courtyard is a 3-
dimensional isometric graph with the frequencies plotted along X-axis in Hz (hertz), time is plotted along Y-axis in
microseconds and the corresponding sound pressure level is plotted along Z-axis in dB (decibels) (Fig 4.2-17). The
111
graph will help find the dominant frequency range of the recorded signal and their reflections off the timeline which
could help in designing the acoustics.
Figure 4.2-17 Harris Hall courtyard setup-1 Sweep noise 3D waterfall graph
The following results were calculated by EASERA program form the data that was collected during the
acoustic field study. EASERA calculated the sound transmission index (STI), AL cons (Articulation Loss of
Consonants), speech transmission index (STI) male, speech transmission index (STI) female (Table 4.2-10).
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009).
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable.
112
STI 0.671
AlCons % 4.494
STI (Male) 0.689
STI (Female) 0.700
RaSTI 0.638
Equiv. STIPa (Male) 0.701
Equiv. STIPa (Female) 0.710
Table 4.2-10 Harris Hall courtyard setup-1 Sweep noise signal STI, AlCons, RaSTI
The Clarity measures of the Sweep noise signal for setup-1 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are plotted in the graph with the frequency along
X- axis in KHz, sound pressure in decibels (dB) along Y-axis (Fig 4.2-18).
Figure 4.2-18 Harris Hall courtyard setup-1 Sweep noise C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80, Grey
– Csplit)
The Clarity measures of the Sweep noise signal for setup-1 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are calculated as per the frequency by EASERA
(Table 4.2-11).
113
125 Hz 250 Hz 500 Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
250Hz-
2kHz
500Hz-
4kHz
dB dB dB dB dB dB dB dB dB
C7 (1/1 Oct.) -19.5 -9 -15.6 -1.6 -4.5 -0.6 1.8 -7.7 -5.6
C50 (1/1 Oct.) -1.8 2.4 1.8 6.6 5.7 7.5 11.7 4.2 5.4
C80 (1/1 Oct.) 2.1 5.3 3.4 8.1 7.2 9.3 14.5 6 7
Csplit (1/1
Oct.) -3.1 -3.1 -0.3 5 3.8 5.3 7.7 1.3 3.5
Table 4.2-11 Harris Hall courtyard setup-1 Sweep noise Clarity measures
The overall results for the Sweep noise signal test for setup-1 at Harris Hall courtyard are calculated in
EASERA. The results are specific to the data collection point for this signal test (Table 4.2-12). Clarity in acoustics
is a parameter to evaluate the degree of separation of successive sounds. It is a ratio of the early sound to the
reverberant sound after a certain amount of time (ADA (Acoustic Design Anhert), 2009). C7 is ratio of direct and
reverberant sound after 7 ms. It can be used to analyze the strength of the direct sound field (ADA (Acoustic Design
Anhert), 2009). C50 measures the speech clarity which is the ratio between the early and late reflections in a space
after 50 ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA
(Acoustic Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation
(ADA (Acoustic Design Anhert), 2009). C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic
Design Anhert), 2009). It is used for evaluating the musical clarity of a space. The C80 value should not exceed +8
dB at any location. Values in white cannot be classified as good or bad values as they are relative to the acoustic
setting and they help us in understanding the overall acoustic performance at the data collection point.
114
Setup-1 Sweep noise impulse response
C7 dB -4.6
C50 dB 3.2
C80 dB 5.8
C35 dB 1.6
D 0.676
L7 dB SPL 72.4
L50 dB SPL 76.6
L80 dB SPL 77.3
L35 dB SPL 76.0
Ltotal dB SPL 78.3
Center time ms 64.15
ST1 dB 1.4
ST2 dB 2.5
Arrival Time ms 62.92
Split Time ms 35
EDT s 1.36
T10 s 1.76
T20 s 1.68
T30 s 1.72
Table 4.2-12 Harris Hall courtyard setup-1 Sweep noise results
Setup-2
The setup-2 had the Yamaha Stagepas 400i and the Audix TM-1 change positions. The acoustic tests were
conducted to collect data on the Audix TM-1 for four types of signals namely Long sweep, MLS, Pink noise and
Sweep noise.
Log sweep signal test
The first test to be conducted was the Log sweep signal test. The results from the test were saves as an
audio (.emd) file which can be opened using EASERA program. EASERA program analyzed the data from the
audio signal and provided results as graphs and tables. The following are the results from the Log sweep signal test
of setup-2 at Harris Hall courtyard.
The Impulse Response graph of the Log sweep test for setup-2 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in mPa (millipascal) (Fig 4.2-19).
115
Figure 4.2-19 Harris Hall courtyard setup-2 Log sweep Impulse response
The Echogram graph of the Log sweep signal test for setup-2 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in dB (decibels) (Fig 4.2-20).
Figure 4.2-20 Harris Hall courtyard setup-2 Log sweep Echogram (Full IR)
The 3D waterfall graph of the Log sweep signal test for setup-2 at Harris Hall courtyard is a 3-dimensional
isometric graph with the frequencies plotted along X-axis in Hz (hertz), time is plotted along Y-axis in microseconds
and the corresponding sound pressure level is plotted along Z-axis in dB (decibels) (Fig 4.2-21).
116
Figure 4.2-21 Harris Hall courtyard setup-2 Log sweep 3D waterfall graph
The following results were calculated by EASERA program form the data that was collected during the
acoustic field study. EASERA calculated the sound transmission index (STI), AL cons (Articulation Loss of
Consonants), speech transmission index (STI) male, speech transmission index (STI) female (Table 4.2-13).
STI 0.730
AlCons % 3.258
STI (Male) 0.736
STI (Female) 0.755
RaSTI 0.680
Equiv. STIPa (Male) 0.740
Equiv. STIPa (Female) 0.753
Table 4.2-13 Harris Hall courtyard setup-2 log sweep STI, AlCons, RaSTI
The Clarity measures of the Log sweep signal for setup-2 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are plotted in the graph with the frequency along
X- axis in KHz, sound pressure in decibels (dB) along Y-axis (Fig 4.2-22).
117
Figure 4.2-22 Harris Hall courtyard setup-2 Log sweep C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80, Grey –
Csplit)
The Clarity measures of the Log sweep signal for setup-2 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are calculated as per the frequency by EASERA
(Table 4.2-14).
125 Hz 250 Hz 500 Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
250Hz-
2kHz
500Hz-
4kHz
dB dB dB dB dB dB dB dB dB
C7 (1/1 Oct.) -18.7 -12.8 -6.7 -2.3 -3.8 -3 0.5 -6.4 -4
C50 (1/1 Oct.) 0 7.1 2.4 6.5 7.9 10.1 12.1 6 6.7
C80 (1/1 Oct.) 2.7 7.9 4.4 7.7 9 11.6 14.6 7.2 8.2
Csplit (1/1
Oct.) -1.1 5.6 1.4 5 6.9 8.5 9.7 4.7 5.4
Table 4.2-14 Harris Hall courtyard setup-2 Log sweep Clarity measures
The overall results for the Log sweep signal test for setup-2 at Harris Hall courtyard are calculated in
EASERA. The results are specific to the data collection point for this signal test (Table 4.2-15). Values in white
cannot be classified as good or bad values as they are relative to the acoustic setting and they help us in
understanding the overall acoustic performance at the data collection point.
118
Setup-2 Log sweep impulse response
C7 dB -5.3
C50 dB 5.4
C80 dB 6.8
C35 dB 4.5
D 0.776
L7 dB SPL 72.6
L50 dB SPL 78.0
L80 dB SPL 78.2
L35 dB SPL 77.8
Ltotal dB SPL 79.1
Center time ms 57.34
ST1 dB 0.9
ST2 dB 1.9
Arrival Time ms 71.40
Split Time ms 35
EDT s 1.38
T10 s 1.88
T20 s 1.82
T30 s 1.80
Table 4.2-15 Harris Hall courtyard setup-2 Log sweep results
MLS signal test
The next test to be conducted was the MLS signal test. The results from the test were saved as an audio
(.emd) file which can be opened using EASERA program. EASERA program analyzed the data from the audio
signal and provided results as graphs and tables. The following are the results from the MLS signal test of setup-2 at
Harris Hall courtyard.
The Impulse Response graph of the MLS test for setup-2 at Harris Hall courtyard is a 2-dimensional graph
where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted along Y-
axis in mPa (millipascal) (Fig 4.2-23).
119
Figure 4.2-23 Harris Hall courtyard setup-2 MLS Impulse response
The Echogram graph of the MLS signal test for setup-2 at Harris Hall courtyard is a 2-dimensional graph
where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted along Y-
axis in dB (decibels) (Fig 4.2-24).
Figure 4.2-24 Harris Hall courtyard setup-2 MLS Echogram (Full IR)
The 3D waterfall graph of the MLS signal test for setup-2 at Harris Hall courtyard is a 3-dimensional
isometric graph with the frequencies plotted along X-axis in Hz (hertz), time is plotted along Y-axis in microseconds
and the corresponding sound pressure level is plotted along Z-axis in dB (decibels) (Fig 4.2-25).
120
Figure 4.2-25 Harris Hall courtyard setup-2 MLS 3D waterfall graph
The following results were calculated by EASERA program form the data that was collected during the
acoustic field study . EASERA calculated the sound transmission index (STI), AL cons (Articulation Loss of
Consonants), speech transmission index (STI) male, speech transmission index (STI) female (Table 4.2-16).
STI 0.720
AlCons % 3.448
STI (Male) 0.725
STI (Female) 0.743
RaSTI 0.671
Equiv. STIPa (Male) 0.730
Equiv. STIPa (Female) 0.742
Table 4.2-16 Harris Hall courtyard setup-2 log sweep STI, AlCons, RaSTI
The Clarity measures of the MLS signal for setup-2 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are plotted in the graph with the frequency along
X- axis in KHz, sound pressure in decibels (dB) along Y-axis (Fig 4.2-26).
121
Figure 4.2-26 Harris Hall courtyard setup-2 MLS C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80, Grey – Csplit)
The Clarity measures of the MLS signal for setup-2 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are calculated as per the frequency by EASERA
(Table 4.2-17).
125 Hz 250 Hz 500 Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
250Hz-
2kHz
500Hz-
4kHz
dB dB dB dB dB dB dB dB dB
C7 (1/1 Oct.) -19.2 -13.1 -6.3 -2.8 -3.3 -4.1 -3.8 -6.4 -4.1
C50 (1/1 Oct.) -0.5 7.1 2.8 6.2 7.2 8.9 12.4 5.8 6.3
C80 (1/1 Oct.) 2.4 7.8 4.8 7.4 8.2 9.8 13.7 7 7.6
Csplit (1/1
Oct.) -1.6 5.5 1.8 4.8 6.4 7.8 10.4 4.6 5.2
Table 4.2-17 Harris Hall courtyard setup-2 MLS Clarity measures
The overall results for the MLS signal test for setup-2 at Harris Hall courtyard are calculated in EASERA.
The results are specific to the data collection point for this signal test (Table 4.2-18). Values in white cannot be
classified as good or bad values as they are relative to the acoustic setting and they help us in understanding the
overall acoustic performance at the data collection point.
122
Setup-2 MLS impulse response
C7 dB -6.4
C50 dB 4.3
C80 dB 5.6
C35 dB 3.5
D 0.728
L7 dB SPL 75.2
L50 dB SPL 81.2
L80 dB SPL 81.5
L35 dB SPL 80.9
Ltotal dB SPL 82.5
Center time ms 86.30
ST1 dB 2.1
ST2 dB 3.1
Arrival Time ms 71.40
Split Time ms 35
EDT s 1.48
T10 s 1.88
T20 s 1.58
T30 s 1.37
Table 4.2-18 Harris Hall courtyard setup-2 MLS results
Pink noise test
The next test was the Pink noise signal test. The results from the test were saved as an audio (.emd) file
which can be opened using EASERA program. EASERA program analyzed the data from the audio signal and
provided results as graphs and tables. The following are the results from the Pink noise signal test of setup-2 at
Harris Hall courtyard.
The Impulse Response graph of the Pink noise test for setup-2 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in mPa (millipascal) (Fig 4.2-27).
123
Figure 4.2-27 Harris Hall courtyard setup-2 Pink noise Impulse response
The Echogram graph of the Pink noise signal test for setup-2 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in dB (decibels) (Fig 4.2-28).
Figure 4.2-28 Harris Hall courtyard setup-2 Pink noise Echogram (Full IR)
The 3D waterfall graph of the Pink noise signal test for setup-2 at Harris Hall courtyard is a 3-dimensional
isometric graph with the frequencies plotted along X-axis in Hz (hertz), time is plotted along Y-axis in microseconds
and the corresponding sound pressure level is plotted along Z-axis in dB (decibels) (Fig 4.2-29).
124
Figure 4.2-29 Harris Hall courtyard setup-2 Pink noise 3D waterfall graph
The following results were calculated by EASERA program form the data that was collected during the
acoustic field study at . EASERA calculated the sound transmission index (STI), AL cons (Articulation Loss of
Consonants), speech transmission index (STI) male, speech transmission index (STI) female (Table 4.2-19).
STI 0.738
AlCons % 3.127
STI (Male) 0.745
STI (Female) 0.765
RaSTI 0.684
Equiv. STIPa (Male) 0.749
Equiv. STIPa (Female) 0.764
Table 4.2-19 Harris Hall courtyard setup-2 log sweep STI, AlCons, RaSTI
The Clarity measures of the Pink noise signal for setup-2 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are plotted in the graph with the frequency along
X- axis in KHz, sound pressure in decibels (dB) along Y-axis (Fig 4.2-30).
125
Figure 4.2-30 Harris Hall courtyard setup-2 Pink noise C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80, Grey –
Csplit)
The Clarity measures of the Pink noise signal for setup-2 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are calculated as per the frequency by EASERA
(Table 4.2-20).
125 Hz 250 Hz 500 Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
250Hz-
2kHz
500Hz-
4kHz
dB dB dB dB dB dB dB dB dB
C7 (1/1 Oct.) -18.9 -12.7 -6.7 -2.2 -3.6 -1.4 2.1 -6.3 -3.5
C50 (1/1 Oct.) -0.2 7.1 2.5 6.7 8.1 10.8 13.6 6.1 7
C80 (1/1 Oct.) 2.6 7.8 4.7 7.8 9.4 12.4 16.1 7.4 8.6
Csplit (1/1
Oct.) -1.4 5.6 1.4 5.2 7.1 9.3 11.7 4.8 5.7
Table 4.2-20 Harris Hall courtyard setup-2 Pink noise Clarity measures
The overall results for the Pink noise signal test for setup-2 at Harris Hall courtyard are calculated in
EASERA. The results are specific to the data collection point for this signal test (Table 4.2-21). Values in white
cannot be classified as good or bad values as they are relative to the acoustic setting and they help us in
understanding the overall acoustic performance at the data collection point.
126
Setup-2 Pink noise impulse response
C7 dB -4.2
C50 dB 5.9
C80 dB 7.2
C35 dB 5.0
D 0.794
L7 dB SPL 83.5
L50 dB SPL 88.1
L80 dB SPL 88.4
L35 dB SPL 87.9
Ltotal dB SPL 89.1
Center time ms 53.73
ST1 dB -0.3
ST2 dB 0.7
Arrival Time ms 1.40
Split Time ms 35
EDT s 1.33
T10 s 1.90
T20 s 1.86
T30 s 1.87
Table 4.2-21 Harris Hall courtyard setup-2 Pink noise results
Sweep noise test
The next test to be conducted was the Pink noise signal test. The results from the test were saved as an
audio (.emd) file which can be opened using EASERA program. EASERA program analyzed the data from the
audio signal and provided results as graphs and tables. The following are the results from the Pink noise signal test
of setup-2 at Harris Hall courtyard.
The Impulse Response graph of the Pink noise test for setup-2 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in mPa (millipascal) (Fig 4.2-31).
127
Figure 4.2-31 Harris Hall courtyard setup-2 Pink noise Impulse response
The Echogram graph of the Pink noise signal test for setup-2 at Harris Hall courtyard is a 2-dimensional
graph where time is plotted along X-axis in microseconds and the corresponding sound pressure level is plotted
along Y-axis in dB (decibels) (Fig 4.2-32).
Figure 4.2-32 Harris Hall courtyard setup-2 Pink noise Echogram (Full IR)
The 3D waterfall graph of the Pink noise signal test for setup-2 at Harris Hall courtyard is a 3-dimensional
isometric graph with the frequencies plotted along X-axis in Hz (hertz), time is plotted along Y-axis in microseconds
and the corresponding sound pressure level is plotted along Z-axis in dB (decibels) (Fig 4.2-33).
128
Figure 4.2-33 Harris Hall courtyard setup-2 Pink noise 3D waterfall graph
The following results were calculated by EASERA program form the data that was collected during the
acoustic field study. EASERA calculated the sound transmission index (STI), AL cons (Articulation Loss of
Consonants), speech transmission index (STI) male, speech transmission index (STI) female (Table 4.2-22).
STI 0.732
AlCons % 3.223
STI (Male) 0.741
STI (Female) 0.761
RaSTI 0.685
Equiv. STIPa (Male) 0.745
Equiv. STIPa (Female) 0.759
Table 4.2-22 Harris Hall courtyard setup-2 log sweep STI, AlCons, RaSTI
The Clarity measures of the Pink noise signal for setup-2 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are plotted in the graph with the frequency along
X- axis in KHz, sound pressure in decibels (dB) along Y-axis (Fig 4.2-34).
129
Figure 4.2-34 Harris Hall courtyard setup-2 Pink noise C7, C50, C80, Csplit graph (Red- C7, Blue – C50, Green – C80, Grey –
Csplit)
The Clarity measures of the Pink noise signal for setup-2 of Harris Hall courtyard study is calculated by
EASERA from the collected data. The C7, C50, C80, Csplit values are calculated as per the frequency by EASERA
(Table 4.2-23).
125 Hz 250 Hz 500 Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
250Hz-
2kHz
500Hz-
4kHz
dB dB dB dB dB dB dB dB dB
C7 (1/1 Oct.) -19.3 -12.9 -6.4 -2.2 -3.4 -2.2 2.1 -6.2 -3.5
C50 (1/1 Oct.) -0.5 6.9 2.8 6.7 8.1 10.4 12.8 6.1 7
C80 (1/1 Oct.) 2.3 7.5 4.5 7.8 9.2 11.9 14.7 7.2 8.3
Csplit (1/1
Oct.) -1.7 5.4 1.8 5.2 7.1 9.1 10.9 4.9 5.8
Table 4.2-23 Harris Hall courtyard setup-2 Pink noise Clarity measures
The overall results for the Pink noise signal test for setup-2 at Harris Hall courtyard are calculated in
EASERA. The results are specific to the data collection point for this signal test (Table 4.2-24). Values in white
cannot be classified as good or bad values as they are relative to the acoustic setting and they help us in
understanding the overall acoustic performance at the data collection point.
130
Setup-2 Pink noise impulse response
C7 dB -5.0
C50 dB 3.9
C80 dB 4.9
C35 dB 3.3
D 0.712
L7 dB SPL 78.8
L50 dB SPL 83.5
L80 dB SPL 83.7
L35 dB SPL 83.3
Ltotal dB SPL 85.0
Center time ms 196.73
ST1 dB -0.1
ST2 dB 1.0
Arrival Time ms 71.44
Split Time ms 35
EDT s 1.37
T10 s 1.73
T20 s 2.04
T30 s 1.91
Table 4.2-24 Harris Hall courtyard setup-2 Pink noise results
4.2.2 Revit and Dynamo
After the development of the Dynamo script for running the acoustic simulation on Revit models, the script
crashed due to the instability of the software, which could not handle the complex calculations associated with the
ray tracing algorithm. The results turned out to be similar even after trying several methods of simplifying the script
to perform the same set of calculations. It was concluded that the current version of Dynamo cannot handle the
complexity of the script. There were no results obtained from Dynamo script.
4.2.3 Acoustic software simulation- EASE
The Harris Hall courtyard was simulated using EASE to validate the results (Fig 4.2-35). The Revit model
used for Dynamo simulation was used as the primary model to convert to other formats for consistency in geometry.
The Revit model was exported as a DXF file and imported in Sketchup to simplify the model by removing surfaces
that won’t receive any reflections; this reduced the simulation run time. The results from the EASE simulation of the
Harris Hall courtyard are described as follows.
131
Figure 4.2-35 Harris Hall courtyard methodology overview
EASE calculated the total sound pressure levels, clarity measurements, first arrival timings, articulation
loss of consonants, speech transmission index for both the setups based on the defined parameters in the model data
(Fig 4.2-36).
Figure 4.2-36 Harris Hall courtyard EASE simulation results overview
Setup-1
Harris Hall courtyard was modelled in Sketchup and the acoustic conditions were simulated in EASE. The
input for the ambient noise collected using Bruel & Kjaer during the acoustic field study was given as the input
noise in EASE (Table 4.2-25).
132
Frequency SPL (Z) dB
100 Hz 85.4
125 Hz 86.25
160 Hz 81.99
200 Hz 75.93
250 Hz 74.98
315 Hz 69.17
400 Hz 69.29
500 Hz 71.5
630 Hz 72.7
800 Hz 70.23
1 kHz 74.46
1.25 kHz 75.58
1.6 kHz 71.89
2 kHz 71.14
2.5 kHz 66.56
3.15 kHz 66.54
4 kHz 65.2
5 kHz 65.02
6.3 kHz 64.86
8 kHz 65.07
10 kHz 62.03
Table 4.2-25 Harris Hall courtyard setup-1 EASE simulation ambient noise input data
Total sound pressure level (SPL)
Total sound pressure level at the setup-1 location of the acoustic field study was simulated in EASE (Fig
4.2-37). EASE calculated the total sound pressure level (SPL) at the location of field study setup-1. Total, average,
minimum and maximum sound pressure levels (SPL) were plotted along Y- axis with frequencies along X-axis (Fig
4.2-38) (Table 4.2-26).
133
Figure 4.2-37 Harris Hall courtyard setup-1 EASE simulation Total SPL mapping
Figure 4.2-38 Harris Hall courtyard setup-1 EASE simulation Total SPL calculation
134
Frequency
Total SPL
(dB)
Average
(dB)
Maximum
(dB)
Minimum
(dB)
100 Hz 80.37 82.46 101.7 79.75
125 Hz 80.34 82.44 101.7 79.73
160 Hz 80.98 83.08 101.68 80.3
200 Hz 81.64 83.72 101.88 80.89
250 Hz 82.31 84.38 102.26 81.5
315 Hz 81.88 84.02 101.18 80.82
400 Hz 81.62 83.78 100.36 80.29
500 Hz 81.51 83.65 99.9 79.91
630 Hz 81.55 83.69 99.87 79.86
800 Hz 81.66 83.79 99.99 79.89
1000 Hz 81.81 83.92 100.12 79.99
1250 Hz 82.22 84.36 101.26 80.47
1600 Hz 82.68 84.85 102.69 80.62
2000 Hz 83.21 85.39 104.49 81.01
2500 Hz 82.44 84.2 102.53 79.01
3150 Hz 81.83 83.11 100.9 77.32
4000 Hz 81.3 82.09 99.4 75.89
5000 Hz 81.58 82.49 100.28 76.53
6300 Hz 81.76 82.84 101.17 77.13
8000 Hz 81.82 83.1 102.07 77.67
10000 Hz 81.23 82.67 102.03 77.4
Table 4.2-26 Harris Hall courtyard setup-1 EASE simulation Total SPL calculation
C7 calculation
C7 is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct
sound field (ADA (Acoustic Design Anhert), 2009). C7 at the setup-1 location of the acoustic field study was
simulated in EASE (Fig 4.2-39).
135
Figure 4.2-39 Harris Hall courtyard setup-1 EASE simulation C7 mapping
EASE calculated the C7 value at the location of field study setup-1. C7 values were plotted along Y- axis
with frequencies along X-axis (Fig 4.2-40) (Table 4.2-27).
Figure 4.2-40 Harris Hall courtyard setup-1 EASE simulation C7 calculation
136
Frequency C7 (dB)
100 Hz -3.7
125 Hz -3.67
160 Hz -3.27
200 Hz -2.86
250 Hz -2.47
315 Hz -1.25
400 Hz -0.12
500 Hz 0.88
630 Hz 1.36
800 Hz 1.75
1000 Hz 2.06
1250 Hz 1.86
1600 Hz 1.55
2000 Hz 1.08
2500 Hz 2.48
3150 Hz 3.69
4000 Hz 4.72
5000 Hz 4.21
6300 Hz 3.62
8000 Hz 2.93
10000 Hz
2.48
Table 4.2-27 Harris Hall courtyard setup-1 EASE simulation
C50 calculation
C50 measures the speech clarity which is the ratio between the early and late reflections in a space after 50
ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic
Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation (ADA
(Acoustic Design Anhert), 2009). C50 at the setup-1 location of the acoustic field study was simulated in EASE
(Fig 4.2-41).
137
Figure 4.2-41 Harris Hall courtyard setup-1 EASE simulation C50 mapping
EASE calculated the C50 value at the location of field study setup-1. C50 values were plotted along Y- axis
with frequencies along X-axis (Fig 4.2-42) (Table 4.2-28).
Figure 4.2-42 Harris Hall courtyard setup-1 EASE simulation C50 calculation
138
Frequency C50 (dB)
100 Hz 7.36
125 Hz 7.41
160 Hz 7.60
200 Hz 7.80
250 Hz 8.00
315 Hz 8.74
400 Hz 9.51
500 Hz 10.28
630 Hz 10.61
800 Hz 10.89
1000 Hz 11.13
1250 Hz 11.10
1600 Hz 11.00
2000 Hz 10.83
2500 Hz 11.83
3150 Hz 12.81
4000 Hz 13.76
5000 Hz 13.42
6300 Hz 13.14
8000 Hz 12.97
10000 Hz 13.31
Table 4.2-28 Harris Hall courtyard setup-1 EASE simulation C50 calculation
C80 calculation
C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space. C80 at the setup-1 location of the acoustic field study was simulated in
EASE (Fig 4.2-43).
139
Figure 4.2-43 Harris Hall courtyard setup-1 EASE simulation C80 calculation
EASE calculated the C50 value at the location of field study setup-1. C50 values were plotted along Y- axis with
frequencies along X-axis (Fig 4.2-44) (Table 4.2-29).
Figure 4.2-44 Harris Hall courtyard setup-1 EASE simulation C80 calculation
140
Frequency C80 (dB)
100 Hz 7.36
125 Hz 7.41
160 Hz 7.60
200 Hz 7.80
250 Hz 8.00
315 Hz 8.74
400 Hz 9.51
500 Hz 10.28
630 Hz 10.61
800 Hz 10.89
1000 Hz 11.13
1250 Hz 11.10
1600 Hz 11.00
2000 Hz 10.83
2500 Hz 11.83
3150 Hz 12.81
4000 Hz 13.76
5000 Hz 13.42
6300 Hz 13.14
8000 Hz 12.97
10000 Hz 13.31
Table 4.2-29 Harris Hall courtyard setup-1 EASE simulation C80 calculation
Setup-2
Harris Hall courtyard was modelled in Sketchup and the acoustics were simulated in EASE. The input for
the ambient noise of setup-2 collected using Bruel & Kjaer during the acoustic field study was given as the input
noise in EASE (Table 4.2-30).
141
Frequency SPL (dB)
100 Hz 72.3
125 Hz 75.01
160 Hz 70.7
200 Hz 66.03
250 Hz 66
315 Hz 61.87
400 Hz 63.16
500 Hz 66.65
630 Hz 66.56
800 Hz 66.85
1 kHz 71.26
1.25 kHz 73.85
1.6 kHz 70.24
2 kHz 71.74
2.5 kHz 67.56
3.15 kHz 67.22
4 kHz 60.5
5 kHz 57.21
6.3 kHz 57.59
8 kHz 56.27
10 kHz 52.72
Table 4.2-30 Harris Hall courtyard setup-2 EASE simulation ambient noise input data
Total sound pressure level (SPL)
Total sound pressure level at the setup-1 location of the acoustic field study was simulated in EASE (Fig
4.2-45). EASE calculated the total sound pressure level (SPL) at the location of field study setup-2. Total, average,
minimum and maximum sound pressure levels (SPL) were plotted along Y- axis with frequencies along X-axis (Fig
4.2-46) (Table 4.2-31).
142
Figure 4.2-45 Harris Hall courtyard setup-2 EASE simulation Total SPL mapping
Figure 4.2-46 Harris Hall courtyard setup-2 EASE simulation Total SPL calculation
143
Frequency Total SPL (dB) Average (dB) Maximum (dB) Minimum (dB)
100 Hz 80.01 82.66 105.31 79.85
125 Hz 79.98 82.64 105.31 79.82
160 Hz 80.59 83.27 105.22 80.38
200 Hz 81.22 83.91 105.14 80.95
250 Hz 81.86 84.56 105.48 81.53
315 Hz 81.32 84.21 104.42 80.85
400 Hz 80.95 83.97 103.68 80.32
500 Hz 80.74 83.83 103.12 79.94
630 Hz 80.78 83.85 103.14 79.92
800 Hz 80.88 83.91 103.24 79.98
1000 Hz 81.05 84.02 103.41 79.95
1250 Hz 81.51 84.44 104.47 80.12
1600 Hz 82.03 84.91 105.68 80.43
2000 Hz 82.63 85.43 107.87 80.92
2500 Hz 81.67 84.19 105.43 78.92
3150 Hz 80.85 83.07 103.7 77.26
4000 Hz 80.13 82.02 102.25 75.84
5000 Hz 80.41 82.43 103.12 76.5
6300 Hz 80.62 82.79 104.03 77.13
8000 Hz 80.69 83.06 104.92 77.69
10000 Hz
80.01 82.66 105.31 79.85
Table 4.2-31 Harris Hall courtyard setup-2 EASE simulation Total SPL calculation
C7 calculation
C7 is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct
sound field (ADA (Acoustic Design Anhert), 2009). C7 at the setup-1 location of the acoustic field study was
simulated in EASE (Fig 4.2-47).
144
Figure 4.2-47 Harris Hall courtyard setup-2 EASE simulation C7 mapping
EASE calculated the C7 value at the location of field study setup-2. C7 values were plotted along Y- axis
with frequencies along X-axis (Fig 4.2-48) (Table 4.2-32).
Figure 4.2-48 Harris Hall courtyard setup-2 EASE simulation C7 calculation
145
Frequency C7 (dB)
100 Hz -5.17
125 Hz -5.14
160 Hz -4.75
200 Hz -4.36
250 Hz -3.98
315 Hz -2.8
400 Hz -1.7
500 Hz -0.71
630 Hz -0.16
800 Hz 0.29
1000 Hz 0.68
1250 Hz 0.54
1600 Hz 0.31
2000 Hz -0.09
2500 Hz 1.13
3150 Hz 2.15
4000 Hz 3.01
5000 Hz 2.45
6300 Hz 1.8
8000 Hz 1.01
10000 Hz
-5.17
Table 4.2-32 Harris Hall courtyard setup-2 EASE simulation C7 calculation
C50 calculation
C50 measures the speech clarity which is the ratio between the early and late reflections in a space after 50
ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic
Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation (ADA
(Acoustic Design Anhert), 2009). C50 at the setup-2 location of the acoustic field study was simulated in EASE
(Fig 4.2-49).
146
Figure 4.2-49 Harris Hall courtyard setup-2 EASE simulation C50 mapping
EASE calculated the C50 value at the location of field study setup-2. C7 values were plotted along Y- axis
with frequencies along X-axis (Fig 4.2-50) (Table 4.2-33).
Figure 4.2-50 Harris Hall courtyard setup-2 EASE simulation C50 calculation
147
Frequency C50 (dB)
100 Hz 6.90
125 Hz 6.94
160 Hz 7.10
200 Hz 7.26
250 Hz 7.43
315 Hz 8.05
400 Hz 8.72
500 Hz 9.39
630 Hz 9.71
800 Hz 10.00
1000 Hz 10.26
1250 Hz 10.29
1600 Hz 10.26
2000 Hz 10.16
2500 Hz 10.96
3150 Hz 11.74
4000 Hz 12.48
5000 Hz 12.15
6300 Hz 11.89
8000 Hz 11.73
10000 Hz 12.04
Table 4.2-33 Harris Hall courtyard setup-2 EASE simulation C50 calculation
C80 calculation
C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space. C80 at the setup-2 location of the acoustic field study was simulated in
EASE (Fig 4.2-51).
148
Figure 4.2-51 Harris Hall courtyard setup-2 EASE simulation C80 mapping
EASE calculated the C80 value at the location of field study setup-2. C7 values were plotted along Y- axis
with frequencies along X-axis (Fig 4.2-552) (Table 4.2-34).
Figure 4.2-52 Harris Hall courtyard setup-2 EASE simulation C80 calculation
149
Frequency C80 (dB)
100 Hz 12.01
125 Hz 12.07
160 Hz 12.23
200 Hz 12.41
250 Hz 12.59
315 Hz 13.27
400 Hz 14.00
500 Hz 14.74
630 Hz 15.06
800 Hz 15.36
1000 Hz 15.62
1250 Hz 15.71
1600 Hz 15.76
2000 Hz 15.74
2500 Hz 16.56
3150 Hz 17.38
4000 Hz 18.20
5000 Hz 17.92
6300 Hz 17.78
8000 Hz 17.85
10000 Hz 18.58
Table 4.2-34 Harris Hall courtyard setup-2 EASE simulation C80 calculation
150
4.3 Los Angeles Memorial Coliseum
Los Angeles Memorial Coliseum was visited 7 times during the 2017-18 college football season. USC
Trojans played 7 home games at the Coliseum. The Extech HD 600 and Sound Analyzer app was used to record data
during the football game. Due to security reasons, advanced sound pressure level meters could not be taken inside
the stadium on game days. The Sound Analyzer app was installed on the mobile device and calibrated using Extech
HD 600 before collecting data in the Coliseum (Fig 4.3-1).
Figure 4.3-1 Los Angeles Memorial Coliseum methodology overview
4.3.1 Real time acoustic study at the Los Angeles Memorial Coliseum during the 2017-18 football season
Data was collected using Coliseum map showing the data collection points using Sound Analyzer mobile
application on Google Pixel mobile device. Los Angeles Memorial Coliseum was visited during the 2017 college
football season. The mobile application was used to collect sound pressure levels at 7 locations namely Student
section-1, Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans (Fig
4.3-2). Data was collected during various times during the game. Data was collected during various in game
scenarios (USC Touchdown, steal, turnover, 3
rd
down etc.) for a period of 20-40 seconds. All the data files from a
game are combined into a single spreadsheet and the peak, average and minimum sound pressure values are reported
151
for each location for all 7 home games (Fig 4.3-3).
Figure 4.3-2 Los Angeles Memorial Coliseum field study data collection points
Figure 4.3-3 Los Angeles Memorial Coliseum field study results overview
152
USC Trojans vs Western Michigan
The USC Trojans vs Western Michigan was the 2017-18 college football season opener. The game started
at 02:00 PM in the afternoon. The recorded attendance during the game was 61125 (University of Southern
California Athletics, 2018). Sound Analyzer mobile application was used to collect sound pressure levels at 7
locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron, North-
west corner, Away fans. Data was collected during various times during the game. Data was collected during
various in game scenarios (USC Touchdown, steal, turnover, 3
rd
down etc.) for a period of 20-40 seconds. All the
data files from a game are combined into a single spreadsheet and the peak, average and minimum sound pressure
values are reported for each location (Table 4.3-1) (Fig 4.3-4) (Fig 4.3-5).
No Data Collection point SPL
63
Hz
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
Global
(dBA)
1 Student section-1
Peak value (dBA)
38.07 44.01 68.5 86.54 89.42 80.05 69.58 68.41 98.82
Minimum (dBA)
35.05 51.3 58.93 62.69 73.11 74.08 58.74 56.54 76.99
Average (dBA)
32.67 43.26 61.02 76.71 78.78 74.6 64.01 54.66 81.91
2
Student section-2
Peak value (dBA)
54.38 59.42 79.34 80.38 83.46 86.87 72.32 73.3 94.4
Minimum (dBA)
25.91 35.12 48.93 59.83 63.53 59.96 51.42 52.76 66.64
Average (dBA)
33.55 49.17 69.02 73.87 75.13 70.55 63.93 60.06 79.03
3 Northwest corner
Peak value (dBA)
39.46 52.26 67.1 75.02 80.9 73.44 66.56 58.74 82.73
Minimum (dBA)
20.1 35.36 49.25 61.45 65.34 64.35 55.72 52.59 69.13
Average (dBA)
24.12 42.38 63.97 65.35 71.53 70.02 62.07 55.54 75.08
4 General Public-1
Peak value (dBA)
23.31 43.82 61.36 73.78 81.57 73.78 63.18 56.28 82.91
Minimum (dBA)
38.25 52.01 58.95 63.18 66.8 66.5 55.75 50.94 71.06
Average (dBA)
36.93 53.45 59.49 62.11 70.71 69.13 60.98 54.82 73.85
5 Titan Tron
Peak value (dBA)
48.84 57.94 69.2 75.57 88.27 84.04 76.97 73.01 90.17
Minimum (dBA)
25.48 36.3 52.7 67.09 71.52 68.73 57.12 56.19 74.45
Average (dBA)
32.77 50.23 67.62 71.73 75.2 72.06 63.71 51.77 78.12
6 General Public-2
Peak value (dBA)
39.46 52.26 67.1 75.02 80.9 73.44 66.56 58.74 82.73
Minimum (dBA)
28.33 42.51 52.09 56.44 53.81 55.34 47.72 42.18 66.63
Average (dBA)
44.24 51.9 67.39 73.4 73.72 69.63 64.49 53.81 78.02
7 Away fans
Peak value (dBA)
28.04 38.27 62.11 66.17 71.3 69.77 62.19 52.27 84.8
Minimum (dBA)
27.74 36.82 50.27 63.07 70.28 63.75 53.26 47.89 71.77
Average (dBA)
35.76 42.65 57.83 69.52 73.59 68.8 60.88 54.12 76.18
Table 4.3-1 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs Western Michigan
153
Figure 4.3-4 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Western Michigan
Figure 4.3-5 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Western Michigan
USC Trojans vs Stanford Cardinals
The USC Trojans vs Stanford Cardinals was the second home game of the 2017-18 college football season.
The game started at 05:30 PM in the afternoon. The recorded attendance during the game was 77614 (University of
Southern California Athletics, 2018). The Sound Analyzer mobile application was used to collect sound pressure
levels at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron,
154
North-west corner, Away fans. Data was collected during various times during the game. Data was collected during
various in game scenarios (USC Touchdown, steal, turnover, 3
rd
down etc.) for a period of 20-40 seconds. All the
data files from a game are combined into a single spreadsheet and the peak, average and minimum sound pressure
values are reported for each location (Table 4.3-2) (Fig 4.3-6) (Fig 4.3-7).
No Data Collection point SPL
63
Hz
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
Global
(dBA)
1 Student section-1
Peak value (dBA)
47.62 58.24 82.12 80.57 85.45 85.16 70.82 66.98 94.68
Minimum (dBA)
32.92 51.56 59.31 63.91 70.15 74.97 64.32 54.77 76.83
Average (dBA)
40.28 50.58 65.41 74.47 78.94 74.34 68.55 56.9 81.61
2
Student section-2
Peak value (dBA)
40.45 48.27 66.16 81.13 79.68 75.76 66.51 60.22 89.82
Minimum (dBA)
32.49 42.48 50.37 56.65 55.71 54.89 45.1 40.14 65.87
Average (dBA)
45.21 56.04 65.72 72.26 76.44 69.78 66.33 56.82 79
3 Northwest corner
Peak value (dBA)
40.28 50.58 65.41 74.47 78.94 74.34 68.55 56.9 81.61
Minimum (dBA)
21.39 32.99 47.54 63.13 64.35 64.35 54.07 52.8 69.03
Average (dBA)
35.14 48.97 53.65 66.69 72.64 65.49 61.49 55.55 74.57
4 General Public-1
Peak value (dBA)
23.22 44.47 59.68 70.73 72.84 70.98 60.73 60.45 76.71
Minimum (dBA)
20.62 34.98 51.65 65.71 66.76 65.2 55.44 51.88 70.94
Average (dBA)
20.42 34.1 48.39 64.5 71.37 66.65 56.11 52.87 73.39
5 Titan Tron
Peak value (dBA)
44.74 51.27 65.74 77.8 83.18 84.02 75.92 71.05 87.6
Minimum (dBA)
32.72 46.86 55.58 64.27 70.42 69.37 57.49 54.96 73.73
Average (dBA)
38.51 57.16 67.66 73.72 74.35 69.99 65.5 58.26 76.51
6 General Public-2
Peak value (dBA)
42.98 54.57 65.74 74.82 75.86 71.35 65.77 57 79.59
Minimum (dBA)
32.11 41.18 47.82 55.76 54.07 55.1 44.81 41.19 65.41
Average (dBA)
35.77 51.81 67.16 71.86 74.7 69.94 62.78 51.33 77.93
7 Away fans
Peak value (dBA)
42.76 53.47 68.84 74.21 76.12 71.6 69.7 58.35 79.99
Minimum (dBA)
35.99 49.97 58 65.71 68.34 65.3 54.31 50.09 69.89
Average (dBA)
34.23 40.14 57.47 67.37 73.15 65.94 58.59 47.19 74.97
Table 4.3-2 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs Stanford Cardinals
155
Figure 4.3-6 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Stanford Cardinals
Figure 4.3-7 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Stanford Cardinals
USC Trojans vs Texas Longhorns
The USC Trojans vs Texas Longhorns was the third home game of the 2017-18 college football season.
The game started at 05:30 PM in the evening. The recorded attendance during the game was 84714 (University of
Southern California Athletics, 2018). The Sound Analyzer mobile application was used to collect sound pressure
156
levels at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron,
North-west corner, Away fans. Data was collected during various times during the game. Data was collected during
various in game scenarios (USC Touchdown, steal, turnover, 3
rd
down etc.) for a period of 20-40 seconds. All the
data files from a game are combined into a single spreadsheet and the peak, average and minimum sound pressure
values are reported for each location (Table 4.3-3) (Fig 4.3-8) (Fig 4.3-9).
No Data Collection point SPL
63
Hz
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
Global
(dBA)
1 Student section-1
Peak value (dBA)
38.18 43.09 68.95 88.61 95.04 79.45 70.27 71.23 99.31
Minimum (dBA)
31.49 52.02 55.56 64.63 73.97 72.63 62.5 63.67 77.06
Average (dBA)
40.1 49.46 69.15 75.88 79.19 73.76 65.78 60.47 82.01
2
Student section-2
Peak value (dBA)
57.02 56.43 71.04 81.42 86.67 83.49 72.2 70.99 94.31
Minimum (dBA)
27.7 37.19 50.22 59.81 63.31 60.38 51.84 54.2 66.74
Average (dBA)
33.36 48.6 68.04 73.01 75.02 72.04 67.83 57.41 79.07
3 Northwest corner
Peak value (dBA)
39.94 53.22 66.8 74.05 82.85 74.38 66.03 57.67 84.07
Minimum (dBA)
22.29 38.51 51.51 62.27 64.04 65.24 55.39 52.66 69.16
Average (dBA)
38.41 49.77 58.28 68.11 71.27 70.03 59.27 59.2 75.1
4 General Public-1
Peak value (dBA)
25.11 45.24 64.99 74.7 79.65 79.62 66.45 59.14 83.46
Minimum (dBA)
35.95 50.2 57.68 64.6 67.21 65.53 54.31 50.57 71.07
Average (dBA)
35.49 52.51 59.37 63.45 69.42 70.8 59.69 51.68 74
5 Titan Tron
Peak value (dBA)
48.36 48.18 63.35 79.19 82.77 79.02 64.88 55.44 90.60
Minimum (dBA)
35.24 49.69 59.95 63.87 68.13 72.16 62.17 56.14 74.55
Average (dBA)
34.9 47.97 66.92 73.44 74.09 71.17 68.08 56.72 78.61
6 General Public-2
Peak value (dBA)
45.04 54.68 66.73 72.99 80.82 74.38 66.75 58.21 82.52
Minimum (dBA)
31.29 39.78 48.37 57.73 56.31 56.11 46.69 43.72 67.2
Average (dBA)
46.96 55.3 65.91 73.58 73.98 69.19 64.52 56.84 78.04
7 Away fans
Peak value (dBA)
28.81 40 62.65 66.44 72.69 71.59 62.71 53.66 83.89
Minimum (dBA)
35.4 52.24 56.74 64.48 68.3 66.56 57.46 53.11 71.9
Average (dBA)
43.61 57.41 65.43 70.71 72.3 68.09 62.41 57.53 76.19
Table 4.3-3 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs Texas Longhorns
157
Figure 4.3-8 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Texas Longhorns
Figure 4.3-9 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Texas Longhorns
USC Trojans vs Oregon State Beavers
The USC Trojans vs Oregon State Beavers was the fourth home game of the 2017-18 college football
season. The game started at 01:00 PM in the afternoon. The recorded attendance during the game was 60314
(University of Southern California Athletics, 2018). Sound Analyzer mobile application was used to collect sound
pressure levels at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2,
158
titantron, North-west corner, Away fans. Data was collected during various times during the game. Data was
collected during various in game scenarios (USC Touchdown, steal, turnover, 3
rd
down etc.) for a period of 20-40
seconds. All the data files from a game are combined into a single spreadsheet and the peak, average and minimum
sound pressure values are reported for each location (Table 4.3-4) (Fig 4.3-10) (Fig 4.3-11).
No Data Collection point SPL
63
Hz
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
Global
(dBA)
1 Student section-1
Peak value (dBA)
40.19 46.43 71.15 84.81 85.6 83.6 70.46 72.08 95.38
Minimum (dBA)
35.72 50.79 57.91 67.74 74.29 71.39 62.79 54.57 76.95
Average (dBA)
33.84 42.96 60.28 77.03 77.89 74.87 64.06 55.5 81.66
2
Student section-2
Peak value (dBA)
41.3 50.88 62.96 77.88 78.32 76.1 60.27 57.32 88.36
Minimum (dBA)
29.77 41.12 48.5 54.33 54.67 56.02 46.66 42.02 66.5
Average (dBA)
41.74 54.42 68.1 73.01 75.94 70.13 64.48 55.26 79
3 Northwest corner
Peak value (dBA)
40.21 51.4 67.46 75.46 76.97 72.88 67.41 59.09 80.66
Minimum (dBA)
19.59 33.25 49.49 62.91 64.96 63.13 58.44 50.84 69.06
Average (dBA)
29.45 53.74 56.84 64.71 71.47 69.51 60.71 60.9 74.63
4 General Public-1
Peak value (dBA)
23.28 45.03 59.12 73.74 75.2 71.71 62.53 58.85 78.75
Minimum (dBA)
22.11 36.15 50.61 62.25 68.69 64.61 54.27 50.9 70.96
Average (dBA)
36.77 52.45 57.51 63.29 71.18 66.99 58.43 53.51 73.41
5 Titan Tron
Peak value (dBA)
47.52 58.75 66.8 75.69 83.09 81.1 75.8 77.12 86.67
Minimum (dBA)
36.93 53.45 59.49 62.11 70.71 69.13 60.98 54.82 73.85
Average (dBA)
39.53 52.51 68.55 72.03 74.52 71 68.58 55.42 76.84
6 General Public-2
Peak value (dBA)
31.43 46.29 71.12 73.89 75.6 71.31 68.13 56.99 79.75
Minimum (dBA)
33.07 39.21 48.82 56.85 54.54 54.97 45.6 39.6 66.12
Average (dBA)
38.74 47.53 67.32 73.94 72.98 69.44 64.83 57.62 77.96
7 Away fans
Peak value (dBA)
35.44 48.67 65.45 74.08 76.41 73.03 69.14 55.49 80.07
Minimum (dBA)
36.31 49.35 58.35 64.7 67.67 66.84 56.55 54.1 70.27
Average (dBA)
34.31 47.28 62.81 70.53 71.48 67.52 61.09 50.12 75.36
Table 4.3-4 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs Oregon State
Beavers
159
Figure 4.3-10 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Oregon State Beavers
Figure 4.3-11 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Oregon State Beavers
160
USC Trojans vs Utah Utes
The USC Trojans vs Utah Utes was the fifth home game of the 2017-18 college football season. The game
started at 05:30 PM in the evening. The recorded attendance during the game was 84714 (University of Southern
California Athletics, 2018). The Sound Analyzer mobile application was used to collect sound pressure levels at 7
locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron, North-
west corner, Away fans. Data was collected during various times during the game. Data was collected during
various in game scenarios (USC Touchdown, steal, turnover, 3
rd
down etc.) for a period of 20-40 seconds. All the
data files from a game are combined into a single spreadsheet and the peak, average and minimum sound pressure
values are reported for each location (Table 4.3-5) (Fig 4.3-12) (Fig 4.3-13).
No Data Collection point SPL
63
Hz
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
Global
(dBA)
1 Student section-1
Peak value (dBA)
42.6 47.75 69.05 81.65 90.36 86.85 75.42 72.73 97.18
Minimum (dBA)
36.03 50.64 60.39 66.41 72.54 73.66 64.76 53.56 76.99
Average (dBA)
37.23 51.2 66.14 75.12 77.44 76.21 72.81 59.52 81.87
2
Student section-2
Peak value (dBA)
47.44 50.08 66.97 77.21 87.24 77.55 63.41 57.07 92.2
Minimum (dBA)
32.03 40.3 48.51 54.74 56.84 56.15 46.14 42.62 66.49
Average (dBA)
41.57 52.72 65.72 74.11 75.18 70.67 66.99 55.48 79.02
3 Northwest corner
Peak value (dBA)
39.57 53.09 66.83 74.13 76.5 75.12 72.83 57.91 81.07
Minimum (dBA)
30.32 46.82 53.63 61.27 64.22 65.21 55.27 53.45 69.11
Average (dBA)
30.77 48.56 57.34 65.66 70.15 70.82 64.9 61.56 74.95
4 General Public-1
Peak value (dBA)
41.78 54.09 66.54 74.05 75.63 72.65 69.65 59.01 79.79
Minimum (dBA)
37.08 52.84 56.36 64.43 67.11 65.69 54.43 51.29 71.02
Average (dBA)
32.72 46.86 55.58 64.27 70.42 69.37 57.49 54.96 73.73
5 Titan Tron
Peak value (dBA)
42.18 49.5 67.84 76.62 82.19 88.18 79.54 75.18 89.99
Minimum (dBA)
37.19 48.76 54.67 67.5 71.25 66.94 59.24 56.59 74.08
Average (dBA)
41.53 53.23 66.88 72.4 73.38 72.47 69.94 58.36 77.91
6 General Public-2
Peak value (dBA)
39.89 51.86 71.32 75.16 76.62 72.48 65.87 60.82 80.62
Minimum (dBA)
32.74 40.44 47.29 54.74 56.37 55.92 46.82 43.96 66.42
Average (dBA)
39.1 50.56 68.06 70.71 74.15 71.14 67.46 54.62 78.01
7 Away fans
Peak value (dBA)
36.3 50.24 65.27 74.35 79.48 75.54 72.43 58.55 82.39
Minimum (dBA)
27.14 44.99 52.32 63.67 67.39 68.28 55.97 52.15 71.48
Average (dBA)
36.09 47.43 65.39 70.72 72.34 67.64 61.9 50.56 76.01
Table 4.3-5 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs Utah Utes
161
Figure 4.3-12 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Utah Utes
Figure 4.3-13 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Utah Utes
USC Trojans vs Arizona Wildcats
The USC Trojans vs Arizona Wildcats was the sixth home game of the 2017-18 college football season.
The game started at 07:45 PM in the evening. The recorded attendance during the game was 70225 (University of
Southern California Athletics, 2018). The Sound Analyzer mobile application was used to collect sound pressure
162
levels at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron,
North-west corner, Away fans. Data was collected during various times during the game. Data was collected during
various in game scenarios (USC Touchdown, steal, turnover, 3
rd
down etc.) for a period of 20-40 seconds. All the
data files from a game are combined into a single spreadsheet and the peak, average and minimum sound pressure
values are reported for each location (Table 4.3-6) (Fig 4.3-14) (Fig 4.3-15).
No Data Collection point SPL
63
Hz
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
Global
(dBA)
1 Student section-1
Peak value (dBA)
38.07 44.01 68.5 86.54 89.42 80.05 69.58 68.41 98.82
Minimum (dBA)
35.05 51.3 58.93 62.69 73.11 74.08 58.74 56.54 76.99
Average (dBA)
32.67 43.26 61.02 76.71 78.78 74.6 64.01 54.66 81.91
2
Student section-2
Peak value (dBA)
54.38 59.42 79.34 80.38 83.46 86.87 72.32 73.3 94.4
Minimum (dBA)
25.91 35.12 48.93 59.83 63.53 59.96 51.42 52.76 66.64
Average (dBA)
33.55 49.17 69.02 73.87 75.13 70.55 63.93 60.06 79.03
3 Northwest corner
Peak value (dBA)
39.46 52.26 67.1 75.02 80.9 73.44 66.56 58.74 82.73
Minimum (dBA)
20.1 35.36 49.25 61.45 65.34 64.35 55.72 52.59 69.13
Average (dBA)
24.12 42.38 63.97 65.35 71.53 70.02 62.07 55.54 75.08
4 General Public-1
Peak value (dBA)
23.31 43.82 61.36 73.78 81.57 73.78 63.18 56.28 82.91
Minimum (dBA)
38.25 52.01 58.95 63.18 66.8 66.5 55.75 50.94 71.06
Average (dBA)
36.93 53.45 59.49 62.11 70.71 69.13 60.98 54.82 73.85
5 Titan Tron
Peak value (dBA)
48.84 57.94 69.2 75.57 88.27 84.04 76.97 73.01 90.17
Minimum (dBA)
25.48 36.3 52.7 67.09 71.52 68.73 57.12 56.19 74.45
Average (dBA)
32.77 50.23 67.62 71.73 75.2 72.06 63.71 51.77 78.12
6 General Public-2
Peak value (dBA)
39.46 52.26 67.1 75.02 80.9 73.44 66.56 58.74 82.73
Minimum (dBA)
28.33 42.51 52.09 56.44 53.81 55.34 47.72 42.18 66.63
Average (dBA)
44.24 51.9 67.39 73.4 73.72 69.63 64.49 53.81 78.02
7 Away fans
Peak value (dBA)
28.04 38.27 62.11 66.17 71.3 69.77 62.19 52.27 84.8
Minimum (dBA)
27.74 36.82 50.27 63.07 70.28 63.75 53.26 47.89 71.77
Average (dBA)
35.76 42.65 57.83 69.52 73.59 68.8 60.88 54.12 76.18
Table 4.3-6 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs Arizona Wildcats
163
Figure 4.3-14 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs Arizona Wildcats
Figure 4.3-15 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs Arizona Wildcats
USC Trojans vs UCLA Bruins
The USC Trojans vs UCLA Bruins was the final home game of the 2017-18 college football season. The
game started at 05:00 PM in the evening. The recorded attendance during the game was 82407 (University of
Southern California Athletics, 2018). Sound Analyzer mobile application was used to collect sound pressure levels
at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron,
164
North-west corner, Away fans. Data was collected during various times during the game. Data was collected during
various in game scenarios (USC Touchdown, takeaway, turnover, 3
rd
down etc.) for a period of 20-40 seconds. All
the data files from a game are combined into a single spreadsheet and the peak, average and minimum sound
pressure values are reported for each location (Table 4.3-7) (Fig 4.3-16) (Fig 4.3-17).
No Data Collection point SPL
63
Hz
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz
Global
(dBA)
1 Student section-1
Peak value (dBA)
46.4 57.06 68.77 80.29 91.67 81.39 70.28 69.18 99.1
Minimum (dBA)
37.39 49.25 66.53 73.93 79.5 71.4 68.83 58.54 81.48
Average (dBA)
42.25 54.24 67.97 73.93 80.66 72.64 65.14 57.89 82.3
2
Student section-2
Peak value (dBA)
55.09 55.28 70.18 80.85 85.09 84.25 73.14 70.43 95.27
Minimum (dBA)
27.12 38.07 48.54 59.51 62.78 61.13 51.61 56.49 66.77
Average (dBA)
39.56 55.91 67.15 72.55 76.1 71.09 64.94 56.46 79.07
3 Northwest corner
Peak value (dBA)
48.3 59.46 68.14 75.26 84.78 83.39 77.65 70.77 87.99
Minimum (dBA)
22.99 33.62 48.49 63.43 64.16 63.18 60.74 51.49 69.18
Average (dBA)
22.94 45.86 58.23 69.45 72.05 70.71 59.96 55.97 75.88
4 General Public-1
Peak value (dBA)
38.96 53.31 66.64 74.62 81.9 73.98 65.96 58.41 83.39
Minimum (dBA)
22.37 37.5 50.8 61.61 68.75 65.35 55.19 51.15 71.13
Average (dBA)
37.19 48.76 54.67 67.5 71.25 66.94 59.24 56.59 74.08
5 Titan Tron
Peak value (dBA)
44.25 53.68 68.85 76.81 81.25 88.75 81.12 73.58 90.38
Minimum (dBA)
35.14 48.97 53.65 66.69 72.64 65.49 61.49 55.55 74.57
Average (dBA)
34.25 46.24 64.22 73.05 74.74 71.41 67.59 56.64 79.43
6 General Public-2
Peak value (dBA)
23.43 42.76 62.56 74.33 80.46 80.24 66 59.05 83.99
Minimum (dBA)
27.8 39.61 48.96 57.61 58.8 56.82 47.91 46.02 68.69
Average (dBA)
40.53 54.34 66.2 73.07 73.93 70.41 65.19 56.1 78.07
7 Away fans
Peak value (dBA)
13.7 28.13 47.15 61.47 80.05 68.54 61.15 55.01 85.02
Minimum (dBA)
26.44 46.68 54.33 64 66.3 68.9 57.76 52.24 72.13
Average (dBA)
39.81 53.26 65.13 70.57 72.83 68.89 62.46 53.53 76.42
Table 4.3-7 Los Angeles Memorial Coliseum field study total SPL at data collection points- USC Trojans vs UCLA Bruins
165
Figure 4.3-16 Los Angeles Memorial Coliseum field study SPL at data collection points- USC Trojans vs UCLA Bruins
Figure 4.3-17 Los Angeles Memorial Coliseum field study photographs- USC Trojans vs UCLA Bruins
4.3.2 Revit & Dynamo
As previously mentioned, after the development of the Dynamo script for running the acoustic simulation
on Revit model of Harris Hall courtyard, the script crashed due to the instability of the software which could not
handle the complex calculations associated with the ray tracing algorithm. The results turned out to be similar even
166
after trying several methods of simplifying the script to perform the same set of calculations. it was concluded that
the current build of Dynamo cannot handle the complexity of the script. A Dynamo script for simulating the acoustic
conditions of Los Angeles Memorial Coliseum could not be developed.
4.3.3 Acoustic software simulation - EASE
Los Angeles Memorial Coliseum was simulated in EASE. The results from EASE simulation are described
below. Two scenarios were considered while simulating the acoustic conditions of the Coliseum. The input for
ambient noise varied in both the scenarios which are taken from the field study data collected at the Coliseum during
the 2017 football season (Fig 4.3-18).
Figure 4.3-18 Los Angeles Memorial Coliseum methodology overview
Scenario-1 data was collected during the course of play. Scenario-2 input data was based on the peak noise
levels measured during in game scenarios (USC Trojans Touchdown, Sack etc.) favoring the home team which
bring the loudest response from the audience (Table 4.3-8). Two sets of simulation results are described based on
each scenario. The same input data will be used for the EASE simulations of the design modification analysis of the
Coliseum. Scenario-2 will have all the speaker sound pressure levels increased by 15 decibels. All mappings of the
Coliseum shown in results are based on 1000 Hz frequency (Fig 4.3-19). However, several listener seats were
placed in the model similar to the locations used for collecting data at the Coliseum. All listeners seats will have
results from Octave bandwidth range (100 Hz – 10000 Hz).
167
Figure 4.3-19 Los Angeles Memorial Coliseum EASE simulation results overview
Frequency Scenario-1 (dB) Scenario-2 (dB)
100 Hz 40.44 55.44
125 Hz 45.99 60.99
160 Hz 54.86 69.86
200 Hz 67.06 82.06
250 Hz 65.43 80.43
315 Hz 68.83 83.83
400 Hz 68.83 83.83
500 Hz 72.37 87.37
630 Hz 81.52 96.52
800 Hz 79.59 94.59
1 kHz 77.88 92.88
1.25 kHz 81.97 96.97
1.6 kHz 81.50 96.50
2 kHz 80.33 95.33
2.5 kHz 73.84 88.84
3.15 kHz 68.11 83.11
4 kHz 62.36 77.36
5 kHz 68.06 83.06
6.3 kHz 73.96 88.96
8 kHz 79.08 94.08
10 kHz 72.07 87.07
Table 4.3-8 Los Angeles Memorial Coliseum EASE simulation input data
Recommended values for the acoustic parameters calculated in the EASE simulation
The following sections will describe the results calculated from the field study and EASE simulations of the Harris
Hall courtyard. The significance and the recommended values of each of the acoustic parameters are explained as
follows:
168
Reverberation time:
The prolongation of sound due to successive reflections within an enclosed space after switching off the
source is called reverberation (Doelle, 1964). There will be a noticeable time before the sound dies when the source
has been stopped. Reverberation time is the time taken for the sound pressure level to drop 60 dB after the source is
stopped.
Clarity measurements
Clarity in acoustics is a parameter to evaluate the degree of separation of successive sounds. It is a ratio of
the early sound to the reverberant sound after a certain amount of time (ADA (Acoustic Design Anhert), 2009). C7
is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct sound field
(ADA (Acoustic Design Anhert), 2009). C50 measures the speech clarity which is the ratio between the early and
late reflections in a space after 50 ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are
considered good (ADA (Acoustic Design Anhert), 2009). Values above – 5 dB are considered good for spaces with
higher reverberation (ADA (Acoustic Design Anhert), 2009). C80 is ratio of direct and late reflections after 80ms
(ADA (Acoustic Design Anhert), 2009). It is used for evaluating the musical clarity of a space. The C80 value
should not exceed +8 dB at any location.
Measurement of clarity based on frequency ranges will aid in understanding the behavior of various types
of sources. Clarity measurements play a major role while designing for musical instruments. Each type of instrument
will produce sound within a frequency range and recommended clarity values.
Articulation loss of consonants
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable.
Speech Transmission Index
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
169
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009).
Total sound pressure level (SPL)
Total sound pressure level (SPL) at the Coliseum mapping at 1000 Hz for scenario-1 was simulated in EASE (Fig
4.3-20). The overall sound pressure levels at each location of the Coliseum can be interpreted from the mapping.
Color scaled mapping can be useful to interpret uneven distribution of sound and speaker system throughout the
space. EASE calculated the sound pressure levels at 7 locations namely Student section-1, Student section-2,
General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation
are exported as a table with the overall peak, average and minimum sound pressure values with the sound pressure
levels for each location (Table 4.3-9) (Fig 4.3-21). Values are color scaled from red to green.
Figure 4.3-20 Los Angeles Memorial Coliseum EASE simulation scenario-1 Total SPL at 1000 Hz mapping
170
FREQUENCY
MAXIMUM
(dBA)
MINIMUM
(dBA)
AVERAGE
(dBA)
STUDENT
SECTION-1
(dBA)
STUDENT
SECTION-2
(dBA)
GENERAL
PUBLIC-1
(dBA)
GENERAL
PUBLIC-2
(dBA)
TITANTRON-1
(dBA)
TITANTRON-2
(dBA)
SOUTHWEST
CORNER (dBA)
PRESS BOX-1
(dBA)
100 Hz 57.11 58.4 57.32 56.79 57.33 57.16 58.24 56.81 56.85 57.11 58.4
125 Hz 61.06 62.57 61.34 60.7 61.35 61.13 62.37 60.72 60.77 61.06 62.57
160 Hz 62.79 64.82 63.25 62.33 63.19 62.85 64.36 62.37 62.43 62.79 64.82
200 Hz 64.25 66.87 64.94 63.67 64.68 64.2 65.82 63.7 63.84 64.25 66.87
250 Hz 66.92 70.25 67.89 66.2 67.7 66.94 69.07 66.29 66.41 66.92 70.25
315 Hz 66.82 70.82 68.11 66.04 67.61 66.84 68.96 66.12 66.28 66.82 70.82
400 Hz 68.76 73.11 70.23 67.96 69.58 68.75 70.93 68.01 68.24 68.76 73.11
500 Hz 72.22 76.65 73.91 71.28 73.96 72.1 75.82 71.42 71.64 72.22 76.65
630 Hz 71.84 77.46 74.26 70.71 74.33 72.23 75.92 70.75 71.09 71.84 77.46
800 Hz 69.73 76.74 73.48 68.53 71.52 69.82 72.03 68.26 69.4 69.73 76.74
1000 Hz 70.09 77.6 74.85 68.75 70.92 69.87 71.82 68.81 70.4 70.09 77.6
1250 Hz 69.9 76.88 73.8 68.52 71.89 69.57 73.01 68.34 69.78 69.9 76.88
1600 Hz 70.88 77.93 74.88 69.52 73 70.47 73.5 69.05 70.73 70.88 77.93
2000 Hz 71.88 79.25 76.19 70.68 73.64 71.89 73.99 69.65 71.8 71.88 79.25
2500 Hz 70.27 78.34 74.42 69.03 71.48 70.17 72.33 68.3 69.94 70.27 78.34
3150 Hz 69.52 78.41 73.7 68.28 70.41 69.74 71.4 67.16 69.06 69.52 78.41
4000 Hz 66.98 75.89 71.75 65.64 67.64 67.21 68.22 64.49 66.84 66.98 75.89
5000 Hz 65.96 74.66 71.05 64.49 66.46 65.95 67.03 63.48 65.92 65.96 74.66
6300 Hz 64.42 73.51 69.69 62.49 65.51 64.06 65.45 62.11 64.49 64.42 73.51
8000 Hz 61.93 70.9 67.41 59.81 63.77 61.06 62.95 59.9 62.04 61.93 70.9
10000 Hz 59.64 67.64 63.4 57.95 63.08 58.54 61.86 58.13 59.16 59.64 67.64
Table 4.3-9 Los Angeles Memorial Coliseum EASE simulation scenario-1 total SPL at listeners seats
Figure 4.3-21 Los Angeles Memorial Coliseum EASE simulation scenario-1 total SPL at listeners seats
171
Total sound pressure level (SPL) at the Coliseum mapping at 1000 Hz for scenario-2 was simulated in
EASE (Fig 4.2-22). The overall sound pressure levels at each location of the Coliseum can be interpreted from the
mapping. Color scaled mapping can be useful to interpret uneven distribution of sound and speaker system
throughout the space. EASE calculated the sound pressure levels at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum sound pressure values with the sound
pressure levels for each location (Table 4.3-10) (Fig 4.3-23).
Figure 4.3-22 Los Angeles Memorial Coliseum EASE simulation scenario-2 Total SPL at 1000 Hz mapping
172
FREQUENC
Y
MAXIMUM
(dBA)
MINIMUM
(dBA)
AVERAGE
(dBA)
STUDENT
SECTION-1
(dBA)
STUDENT
SECTION-2
(dBA)
GENERAL
PUBLIC-1
(dBA)
GENERAL
PUBLIC-2
(dBA)
TITANTRON
-1 (dBA)
TITANTRON
-2 (dBA)
SOUTHWES
T CORNER
(dBA)
PRESS BOX-
1 (dBA)
100 Hz 98.6 84.31 84.93 85.85 85 84.65 85.34 85.14 86.4 84.71 84.71
125 Hz 103.08 88.17 88.89 89.97 88.99 88.56 89.38 89.12 90.56 88.64 88.64
160 Hz 105.12 89.65 90.61 92.08 90.81 90.19 91.26 90.88 92.61 90.31 90.33
200 Hz 107.08 90.82 92.06 94.06 92.41 91.52 92.79 92.25 94.1 91.66 91.76
250 Hz 110.09 93.19 94.72 97.44 95.26 94.01 95.9 95.04 97.44 94.28 94.37
315 Hz 109.07 92.75 94.6 97.85 95.33 93.84 95.83 94.97 97.35 94.15 94.26
400 Hz 108.76 94.57 96.53 100.08 97.36 95.76 97.81 96.88 99.32 96.03 96.24
500 Hz 113.13 97.77 99.99 103.67 100.99 99.04 102.31 100.24 104.34 99.48 99.71
630 Hz 112.41 96.25 99.59 104.77 101.35 98.26 102.79 100.53 104.49 98.92 99.32
800 Hz 111.5 92.85 97.45 104.23 100.4 95.76 99.93 98.14 100.55 96.51 97.8
1000 Hz 110.92 92.64 97.76 104.76 101.45 95.82 99.24 98.16 100.31 97.1 98.88
1250 Hz 110.49 93.37 97.6 104.01 100.42 95.82 100.33 97.84 101.57 96.55 98.16
1600 Hz 112.71 94.31 98.6 105.28 101.58 96.8 101.45 98.74 102.05 97.25 99.13
2000 Hz 114.19 94.78 99.59 107.05 103.06 97.73 102.08 100.26 102.53 97.87 100.24
2500 Hz 113.39 93.32 97.97 106.04 101.19 96.06 99.9 98.54 100.87 96.52 98.37
3150 Hz 113.44 92.51 97.23 106.31 100.6 95.2 98.82 98.15 99.94 95.38 97.48
4000 Hz 110.97 90.06 94.69 104.02 98.73 92.59 96.03 95.63 96.73 92.69 95.29
5000 Hz 110.34 89.37 93.68 102.8 98.17 91.54 94.86 94.36 95.52 91.65 94.35
6300 Hz 109.19 88.61 92.17 101.53 96.58 89.86 93.94 92.39 93.91 90.21 92.87
8000 Hz 107.5 86.81 89.72 98.96 94.23 87.45 92.24 89.27 91.36 87.93 90.37
10000
Hz
105.48 85.62 87.47 95.29 90.31 85.79 91.58 86.55 90.28 86.05 87.27
Table 4.3-10 Los Angeles Memorial Coliseum EASE simulation scenario-2 total SPL at listeners seats
Figure 4.3-23 Los Angeles Memorial Coliseum EASE simulation scenario-2 Total SPL at listeners seats
173
First arrival mapping
First arrival timing mapping calculates the arrival time for any location from the nearest sound source.
EASE calculated the first arrival timings at 7 locations namely Student section-1, Student section-2, General
audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation are
exported as a table with the overall peak, average and minimum first arrival timings with the first arrival timings for
each location (Table 4.3-11) (Fig 4.3-24). Values in green are acceptable, values in orange are fair and values in red
are unacceptable.
Figure 4.3-24 Los Angeles Memorial Coliseum EASE simulation first arrival mapping
First Arrival (ms)
Maximum
409.3
Minimum
0
Average
200.79
Student section-1
93.36
Student section-2
159.63
General Public-1
182.87
General Public-2
57.26
Titantron-1
73.98
Titantron-2
31.23
Southwest corner
126.7
Press Box-1
227.66
Table 4.3-11 Los Angeles Memorial Coliseum EASE simulation first arrival calculation at listeners seats
174
C7 mapping
C7 is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct
sound field (ADA (Acoustic Design Anhert), 2009). Values above -15 dB are considered good. Values closer to 0
dB are considered better (ADA (Acoustic Design Anhert), 2009). C7 mapping at the Coliseum for 1000 Hz was
simulated in EASE (Fig 4.3-25). EASE calculated the C7 values at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum C7 values with the C7 values for
each location (Table 4.3-12) (Fig 4.3-26). Values in green are recommended values, values in orange are
moderately acceptable and values in red are unacceptable values.
Figure 4.3-25 Los Angeles Memorial Coliseum EASE simulation C7 mapping at 1000 Hz
175
FREQUENCY
MAXIMUM (dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1 (dB)
STUDENT
SECTION-2 (dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 12.3 -24.79 -12.96 -3.09 -7.51 -17.9 -9.53 -12.54 -5.1 -14.63 -13.12
125 Hz 12.85 -23.99 -12.24 -2.23 -6.61 -17.35 -8.75 -11.94 -4.41 -13.87 -12.19
160 Hz 13.26 -22.65 -10.86 -0.55 -4.82 -16.22 -7.43 -11.03 -3.34 -12.52 -10.43
200 Hz 13.74 -21.39 -9.54 0.96 -3.26 -15.18 -6.46 -10.68 -2.77 -11.58 -8.89
250 Hz 14.43 -22.78 -8.77 2.61 -1.69 -15.83 -4.95 -9.99 -1.51 -10.44 -7.33
315 Hz 14.03 -21.84 -7.8 4.08 -0.22 -14.15 -4.43 -9.31 -1.19 -9.56 -5.91
400 Hz 11.95 -22.84 -7.45 4.79 0.41 -13.49 -4.29 -9.39 -1.18 -9.63 -5.31
500 Hz 13.09 -26.78 -7.16 5.29 1.33 -14.66 -2.61 -9.57 0.61 -8.45 -4.36
630 Hz 15.6 -31.6 -6.04 8.07 4.03 -16.98 -0.33 -7.66 2.14 -6.48 -1.74
800 Hz 16.95 -32.74 -6.09 10.81 7.06 -21.14 -0.21 -9.62 0.1 -6.4 1.32
1000 Hz 16.7 -31.2 -4.94 11.85 8.78 -19.32 -3.42 -10.97 -2.39 -6.52 3
1250 Hz 16.21 -27.69 -4.86 10.49 7 -16.5 -0.88 -10.6 0.9 -7.07 1.23
1600 Hz 17.68 -27.91 -5.27 10.63 7.16 -19.03 0.05 -12.02 0.33 -8.03 1.35
2000 Hz 17.69 -31.61 -5.42 11.42 7.99 -19.99 -0.96 -11.76 -1.08 -7.59 2.17
2500 Hz 18.81 -35.41 -6.24 12.14 7.79 -22.27 -0.69 -13.88 -0.98 -7.62 1.79
3150 Hz 19.41 -38.32 -7.14 13.06 7.88 -25.68 -1.24 -15.22 -2.38 -8.78 1.69
4000 Hz 19.56 -41 -7.44 13.1 8.57 -25.58 -1.97 -15.73 -4.06 -8.08 2.2
5000 Hz 19.82 -43.89 -8.57 12.71 8.73 -29.18 -2.05 -16.03 -4.71 -8.2 2
6300 Hz 19.54 -44.72 -9.42 12.43 8.23 -28.58 -0.67 -16.63 -3.34 -9.36 1.13
8000 Hz 19.71 -50.2 -11.6 11.62 7.74 -31.57 0.19 -16.25 -2.34 -10.23 0.07
10000
Hz
19.74 -50.94 -13.75 9.39 4.23 -30.34 2.23 -15.14 0.56 -13.03 -4.28
Table 4.3-12 Los Angeles Memorial Coliseum EASE simulation C7 calculation at listeners seats
Figure 4.3-26 Los Angeles Memorial Coliseum EASE simulation C7 calculation at listeners seats
176
C50 mapping
C50 measures the speech clarity which is the ratio between the early and late reflections in a space after 50
ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic
Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation (ADA
(Acoustic Design Anhert), 2009). C50 mapping at the Coliseum for 1000 Hz was simulated in EASE (Fig 4.3-27).
EASE calculated the C50 values at 7 locations namely Student section-1, Student section-2, General audience-1,
General audience-2, titantron, North-west corner, Away fans. The results from the simulation are exported as a table
with the overall peak, average and minimum C50 values with the C50 values for each location (Table 4.3-13) (Fig
4.3-28). Values in green are recommended values, values in light green are moderately acceptable and values in red
are unacceptable values.
Figure 4.3-27 Los Angeles Memorial Coliseum EASE simulation C50 mapping at 1000 Hz
177
FREQUENCY
MAXIMUM
(dB)
MINIMUM
(dB)
AVERAGE
(dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1
(dB)
GENERAL
PUBLIC-2
(dB)
TITANTRON-
1 (dB)
TITANTRON-
2 (dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 12.56 -21.54 -9.31 -2.23 -5.82 -14.12 -6.39 -7.93 -3.02 -9.94 -9.21
125 Hz 13.13 -21.08 -8.65 -1.38 -4.99 -13.58 -5.65 -7.3 -2.3 -9.32 -8.49
160 Hz 13.58 -20 -7.44 0.27 -3.38 -12.54 -4.46 -6.38 -1.24 -8.32 -7.2
200 Hz 14.08 -18.7 -6.31 1.75 -1.96 -11.59 -3.63 -6.02 -0.8 -7.56 -6.04
250 Hz 14.82 -20.03 -5.57 3.4 -0.48 -12.02 -2.12 -5.28 0.64 -6.76 -4.81
315 Hz 14.51 -18.9 -4.64 4.89 0.94 -10.55 -1.73 -4.64 0.85 -6.11 -3.65
400 Hz 12.51 -20.04 -4.19 5.67 1.63 -9.97 -1.43 -4.6 1.06 -5.89 -3.03
500 Hz 13.69 -23.34 -3.72 6.26 2.57 -10.91 0.79 -4.54 3.57 -5.08 -2.16
630 Hz 16.34 -25.35 -2.69 8.98 5.09 -12.84 2.41 -2.9 4.17 -4.09 -0.1
800 Hz 17.69 -29.02 -2.26 11.67 7.97 -15.53 0.99 -5.62 0.89 -4.34 2.52
1000 Hz 17.52 -27.21 -1.43 12.72 9.67 -14.49 -1.62 -7.25 -0.39 -4.65 4.08
1250 Hz 17.05 -23.95 -1.59 11.44 8.01 -12.37 1.82 -6.13 2.78 -4.5 2.55
1600 Hz 18.51 -24.81 -1.9 11.59 8.19 -14.31 2.07 -7.45 1.92 -4.99 2.71
2000 Hz 18.52 -28.22 -1.77 12.37 8.98 -14.97 1.52 -7.6 0.2 -4.72 3.43
2500 Hz 19.67 -31.86 -2.12 13.11 8.82 -16.17 1.13 -9.12 0.19 -4.79 3.15
3150 Hz 20.29 -35.59 -2.36 14.04 8.93 -17.32 0.63 -10.4 -0.75 -5.29 3.09
4000 Hz 20.53 -37.41 -2.34 14.15 9.67 -17.22 0.04 -10.66 -2.67 -4.62 3.63
5000 Hz 20.89 -40.81 -2.51 13.88 9.94 -17.29 -0.32 -10.47 -3.07 -4.32 3.57
6300 Hz 20.77 -40.61 -2.7 13.77 9.64 -15.7 1.16 -9.88 -1.52 -4.12 3.07
8000 Hz 21.17 -46.13 -3.08 13.23 9.44 -14.4 2.41 -8.41 -0.14 -3.52 2.56
10000
Hz
21.61 -47.98 -3.61 11.5 6.68 -12.7 5.35 -6.2 3.26 -2.62 0.37
Table 4.3-13 Los Angeles Memorial Coliseum EASE simulation C50 calculation at listeners seats
Figure 4.3-28 Los Angeles Memorial Coliseum EASE simulation C50 calculation at listeners seats
178
C80 mapping
C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space. C80 mapping at the Coliseum for 1000 Hz was simulated in EASE (Fig
4.3-29). EASE calculated the C80 values at 7 locations namely Student section-1, Student section-2, General
audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation are
exported as a table with the overall peak, average and minimum C80 values with the C80 values for each location
(Table 4.3-14) (Fig 4.3-30). Values in green are recommended values, values in light green are moderately
acceptable and values in red are unacceptable values.
Figure 4.3-29 Los Angeles Memorial Coliseum EASE simulation C80 mapping at 1000 Hz
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FREQUENCY
MAXIMUM
(dB)
MINIMUM
(dB)
AVERAGE
(dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1
(dB)
GENERAL
PUBLIC-2
(dB)
TITANTRON-
1 (dB)
TITANTRON-
2 (dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 12.86 -19.74 -6.41 -1.35 -4.33 -8.99 -4.79 -5.86 -2.05 -7.12 -6.69
125 Hz 13.47 -19.17 -5.74 -0.5 -3.53 -8.45 -4.08 -5.25 -1.33 -6.53 -6.02
160 Hz 13.97 -18 -4.58 1.14 -2.02 -7.58 -2.95 -4.33 -0.26 -5.6 -4.86
200 Hz 14.49 -16.84 -3.53 2.61 -0.68 -6.85 -2.13 -3.87 0.24 -4.87 -3.84
250 Hz 15.29 -17.41 -2.66 4.25 0.75 -6.71 -0.79 -3.22 1.6 -4.17 -2.72
315 Hz 15.07 -15.91 -1.74 5.77 2.14 -5.92 -0.38 -2.63 1.86 -3.61 -1.69
400 Hz 13.16 -15.25 -1.22 6.64 2.9 -5.37 -0.01 -2.45 2.14 -3.27 -1.03
500 Hz 14.41 -16.1 -0.64 7.31 3.88 -5.57 1.98 -2.29 4.51 -2.59 -0.18
630 Hz 17.8 -16.63 0.46 9.99 6.24 -6.89 3.27 -1.43 4.88 -2.09 1.54
800 Hz 19.08 -17.42 1.3 12.62 8.98 -8.54 1.72 -4.07 1.54 -2.59 3.82
1000 Hz 18.44 -16.46 1.94 13.68 10.66 -8.45 -0.8 -5.4 0.28 -3.07 5.25
1250 Hz 18.2 -17 1.62 12.49 9.14 -6.91 2.64 -4.11 3.46 -2.47 3.97
1600 Hz 19.49 -17.35 1.54 12.67 9.33 -7.52 2.89 -5.05 2.65 -2.75 4.16
2000 Hz 19.48 -18.26 1.81 13.42 10.07 -8.23 2.29 -5.54 0.89 -2.55 4.8
2500 Hz 20.67 -18.7 1.74 14.2 9.98 -8.32 2.02 -6.48 0.92 -2.66 4.62
3150 Hz 21.32 -19.05 1.83 15.14 10.1 -8.53 1.58 -7.43 0 -2.87 4.6
4000 Hz 21.66 -20.07 2.01 15.33 10.91 -8.18 1.07 -7.46 -1.7 -2.18 5.18
5000 Hz 22.18 -21.13 2.21 15.2 11.31 -7.5 0.87 -6.9 -1.91 -1.66 5.28
6300 Hz 22.26 -22.5 2.31 15.31 11.25 -5.53 2.55 -5.62 -0.13 -0.97 5.11
8000 Hz 22.95 -24.99 2.53 15.08 11.38 -3.64 4.04 -3.57 1.64 0.1 5.07
10000 Hz 23.87 -32.19 2.49 13.88 9.3 -1.39 7.72 -0.45 5.74 1.82 4
Table 4.3-14 Los Angeles Memorial Coliseum EASE simulation C80 calculation at listeners seats
Figure 4.3-30 Los Angeles Memorial Coliseum EASE simulation C80 calculation at listeners seats
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Articulation loss of consonants (ALcons) mapping:
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable. EASE calculated the AL cons at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum AL cons percentages with the AL cons
percentages for each location (Table 4.3-15) (Fig 4.3-31).
Figure 4.3-31 Los Angeles Memorial Coliseum EASE simulation Articulation loss of consonants mapping
Articulation Loss of Consonants (ALC) (%)
Maximum
100
Minimum
1
Average
7.97
Student section-1
1.3
Student section-2
2.3
General Public-1
14.89
General Public-2
7.69
Titantron-1
11.94
Titantron-2
7.68
Southwest corner
14.74
Press Box-1
5.33
Table 4.3-15 Los Angeles Memorial Coliseum EASE simulation Articulation loss of consonants calculation at listeners seats
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Speech transmission index (STI) mapping:
Speech Transmission Index is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009). EASE calculated the speech transmission index
at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron,
North-west corner, Away fans. The results are exported as a table with the overall peak, average and minimum
speech transmission index with the speech transmission index for each location (Table 4.3-16) (Fig 4.3-32).
Figure 4.3-32 Los Angeles Memorial Coliseum EASE simulation speech transmission index (STI) mapping
Speech Transmission Index (STI)
Maximum
0.978
Minimum
0
Average
0.602
Student section-1
0.899
Student section-2
0.795
General Public-1
0.45
General Public-2
0.572
Titantron-1
0.491
Titantron-2
0.572
Southwest corner
0.452
Press Box-1
0.639
Table 4.3-16 Los Angeles Memorial Coliseum EASE simulation speech transmission index (STI) at listeners seats
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4.4 Summary
Complex calculations associated with the ray tracing algorithm of the Dynamo script crashed the software
program making it not possible to complete the script. The methodology was modified to analyze the acoustics of
the two case study spaces.
Results from acoustic field study and EASE simulations of Harris Hall courtyard and the Los Angeles
Memorial Coliseum were described in this chapter. Results from two setups with four types of signal measurements
(Log sweep, MLS, Pink noise, Sweep noise) at Harris Hall courtyard were exported as tables and graphs from
EASERA sound measurement program. EASERA calculated the speech transmission index (STI), articulation loss
of consonants (AL cons), speech transmission index (STI) male, speech transmission index (STI) female, RASTI
(Room Acoustic STI), impulse response graph, clarity measurements (C7, C50, C80) from the recorded audio file
(.emd). EASE simulations calculated the total sound pressure level, first arrival time, clarity measurements (C7,
C50, C80), speech transmission index (STI), articulation loss of consonants (AL cons) and reverberation time at the
data collection points of the field study and provided a colored index mapping of each of the parameters.
Results from the Los Angeles Memorial Coliseum field study were exported as Excel spreadsheets from the
Sound Analyzer app. The results are presented as tables with a map of the Coliseum seating chart showing the data
collection points and their sound pressure values during various scenarios during the football games. Observations
made during the game were instrumental in developing the EASE model of the Coliseum. EASE simulations
calculated the total sound pressure level, first arrival time, clarity measurements (C7, C50, C80), speech
transmission index (STI), articulation loss of consonants (AL cons) and reverberation time at the data collection points
of the field study and provided a colored index mapping of each of the parameters. The results from the simulations
and field study are analyzed in chapter 5. Based on the analysis, two design retrofit options were proposed that are
explained in chapter 6.
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Chapter 5: Discussion
5.1 Overview
The results from the acoustic field study and EASE simulations of Harris Hall courtyard and the Los
Angeles Memorial Coliseum were documented in the previous chapter. The studies provided a wide range of data.
Although the purpose of conducting the field study at courtyard at was to aid in developing a Dynamo script for its
scale, the instability of Dynamo and crashing during the implementation of the workflow. Hence, the study focused
on the EASE evaluation of the Coliseum and developing two retrofit options which are described in chapter 6. The
results from the field study of Los Angeles Memorial Coliseum didn’t provide as much data as the Harris Hall
courtyard.
Figure 5.1-1 Overall methodology overview
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5.2 Harris Hall courtyard at the University of Southern California
The acoustic field study at the Harris Hall courtyard of the University of Southern California was
conducted to collect acoustic data that can be used as a benchmark for the Dynamo script results and the acoustic
simulation results. The results from EASERA and EASE have been summarized together to compare the results
from both the methods.
Figure 5.2-1 Harris Hall courtyard acoustic field study methodology overview
5.2.1 Observations from acoustic study results of Harris Hall courtyard at the University of Southern
California
The setup for the study included Audix TM-1, Rolland OCTACAPTURE and the Yamaha Stagepas 400i
connected to perform the various acoustic testing. The Bruel and Kjaer type 2250 hand-held analyzer was used to
calibrate the test microphone for the study. EASERA was used to generate four types of test signals namely Log
sweep, MLS (Maximum Length Sequence) signal, Pink noise and Sweep noise. Two configurations of the
equipment were setup and the four signal tests were performed at each location. EASERA recorded the signals
during each test and provided the impulse graphs, 3d waterfall graphs, clarity measurements (C7, C50, C80), arrival
time, EDT (Early Decay Time), articulation loss of consonants (Al cons), speech transmission index (STI, RaSTI) for
each case (Fig 5.2-2).
185
Figure 5.2-2 Harris Hall courtyard acoustic field study results overview
EASE calculated the total, average, maximum and minimum SPL, C7, C50 and C80 at setup-1 location
(Fig 5.2-3).
Figure 5.2-3 Harris Hall courtyard EASE simulation results overview
Recommended values for the acoustic parameters calculated in the field study using EASERA
The significance and the recommended values of each of the acoustic parameters are explained as follows (Table
5.2-1).
Impulse response graph
The impulse response is plotted in decibels (dB) along Y-axis with the frequency plotted in X-axis. It helps
in finding similar reflections and sound impulse patterns at the measuring location which will help in identifying any
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acoustic defects such as late reflections, flutter echoes and deciding on treatment. Early reflections can be identified
by looking for similar patterns with reduced energy.
3d waterfall graph
The 3d waterfall graph will help find the dominant frequency range of the recorded signal and their
reflections off the timeline, which could help in designing the acoustics.
Speech Transmission Index
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009).
Articulation loss of consonants
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable.
Clarity measurements
Clarity in acoustics is a parameter to evaluate the degree of separation of successive sounds. It is a ratio of
the early sound to the reverberant sound after a certain amount of time (ADA (Acoustic Design Anhert), 2009). C7
is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct sound field
(ADA (Acoustic Design Anhert), 2009). C50 measures the speech clarity which is the ratio between the early and
late reflections in a space after 50 ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are
considered good (ADA (Acoustic Design Anhert), 2009). Values above – 5 dB are considered good for spaces with
higher reverberation (ADA (Acoustic Design Anhert), 2009). C80 is ratio of direct and late reflections after 80ms
(ADA (Acoustic Design Anhert), 2009). It is used for evaluating the musical clarity of a space. The C80 value
should not exceed +8 dB at any location.
187
Measurement of clarity based on frequency ranges will aid in understanding the behavior of various types
of sources. Clarity measurements play a major role while designing for musical instruments. Each type of instrument
will produce sound within a frequency range and recommended clarity values.
RECOMMENDED VALUES FOR ACOUSTIC VARIABLES
C7 Above -15 good, better if closer to 0
C50 Above -5 is considered good
C80 Not above +8
AlCons
0-3% - excellent,
3-7% – good,
7-15% - fair,
15-33% - poor
Above 33% - unacceptable
STI 0.75-1 – excellent
0.6-0.75 – good
0.45-0.6 – fair
0.3-0.45 – poor
0-0.3 – unacceptable
STI (Male)
STI (Female)
RaSTI
Equiv. STIPa (Male)
Equiv. STIPa (Female)
Table 5.2-1 Recommended values for acoustic variables (ADA (Acoustic Design Anhert), 2009)
5.2.2 Harris Hall courtyard setup-1
EASERA was used to generate four types of test signals namely Log sweep, MLS (Maximum Length
Sequence) signal, Pink noise and Sweep noise at setup-1 location. EASERA recorded the signals during each test
and provided the impulse response graphs, 3d waterfall graphs, clarity measurements (C7, C50, C80), arrival time,
EDT (Early Decay Time), articulation loss of consonants (Al cons), speech transmission index (STI, RaSTI) for each
case (Table 5.2-2). Values in dark green are acceptable values, values in light green are acceptable values, values in
yellow indicate fair and the values in red are unacceptable. Values in white cannot be classified as good or bad
values as they are relative to the acoustic setting and they help us in understanding the overall acoustic performance
at the data collection point.
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LOG SWEEP MLS PINK NOISE SWEEP NOISE
C7 dB 2.5 -6 -4.5 -4.6
C50 dB 13 2.1 2.7 3.2
C80 dB 16.5 4.6 5.1 5.8
C35 dB 9.7 0.8 1.2 1.6
D 0.952 0.619 0.649 0.676
L7 dB SPL 66.5 73.6 83.4 72.4
L50 dB SPL 68.3 78.5 87.3 76.6
L80 dB SPL 68.4 79.2 88 77.3
L35 dB SPL 68 77.9 86.8 76
Ltotal dB SPL 68.5 80.6 89.2 78.3
Center time ms 13.64 136.48 123.44 64.15
ST1 dB -4.4 2.3 0.8 1.4
ST2 dB -4.2 3.4 1.9 2.5
Arrival Time ms 63.08 63.1 63.06 62.92
Split Time ms 35 35 35 35
EDT s 1.48 1.45 1.34 1.36
T10 s 1.88 1.91 1.76 1.76
T20 s 1.58 1.76 1.68 1.68
T30 s 1.37 2.06 1.63 1.72
AlCons % 4.292 5.78 5.926 4.494
STI 0.679 0.625 0.62 0.671
STI (Male) 0.698 0.642 0.634 0.689
STI (Female) 0.711 0.649 0.64 0.7
RaSTI 0.646 0.605 0.601 0.638
Equiv. STIPa (Male) 0.711 0.657 0.644 0.701
Equiv. STIPa (Female) 0.722 0.662 0.646 0.71
Table 5.2-2 Harris Hall courtyard setup-1 field study results
EASE calculated the total, average, maximum and minimum SPL, C7, C50 and C80 at setup-1 location
(Table 5.2-3). Total SPL values are color scaled from 55 dB – 115 dB in red to green. Clarity values in dark green
are acceptable, values in light green are slightly out of range from acceptable range, values in yellow are fair and
values in red are unacceptable. Values in white cannot be classified as good or bad values as they are relative to the
acoustic setting and they help us in understanding the overall acoustic performance at the data collection point.
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EASE SIMULATION SETUP-1
Frequency
Total SPL
C7 (dB) C50 C80
Current Pos. Average Maximum Minimum
100 Hz 80.37 82.46 101.7 79.75 -3.7 7.36 7.36
125 Hz 80.34 82.44 101.7 79.73 -3.67 7.41 7.41
160 Hz 80.98 83.08 101.68 80.3 -3.27 7.6 7.6
200 Hz 81.64 83.72 101.88 80.89 -2.86 7.8 7.8
250 Hz 82.31 84.38 102.26 81.5 -2.47 8 8
315 Hz 81.88 84.02 101.18 80.82 -1.25 8.74 8.74
400 Hz 81.62 83.78 100.36 80.29 -0.12 9.51 9.51
500 Hz 81.51 83.65 99.9 79.91 0.88 10.28 10.28
630 Hz 81.55 83.69 99.87 79.86 1.36 10.61 10.61
800 Hz 81.66 83.79 99.99 79.89 1.75 10.89 10.89
1000 Hz 81.81 83.92 100.12 79.99 2.06 11.13 11.13
1250 Hz 82.22 84.36 101.26 80.47 1.86 11.1 11.1
1600 Hz 82.68 84.85 102.69 80.62 1.55 11 11
2000 Hz 83.21 85.39 104.49 81.01 1.08 10.83 10.83
2500 Hz 82.44 84.2 102.53 79.01 2.48 11.83 11.83
3150 Hz 81.83 83.11 100.9 77.32 3.69 12.81 12.81
4000 Hz 81.3 82.09 99.4 75.89 4.72 13.76 13.76
5000 Hz 81.58 82.49 100.28 76.53 4.21 13.42 13.42
6300 Hz 81.76 82.84 101.17 77.13 3.62 13.14 13.14
8000 Hz 81.82 83.1 102.07 77.67 2.93 12.97 12.97
10000 Hz 81.23 82.67 102.03 77.4 2.48 13.31 13.31
Table 5.2-3 Harris Hall courtyard setup-1 EASE simulation results
EASERA provided a wide range of data and graphs which were described in chapter 4. The data was
summarized to draw comparison from the EASE simulation results. Results show that the Clarity values are similar
to the field study measurements.
5.2.3 Harris Hall courtyard setup-2
EASERA was used to generate four types of test signals namely Log sweep, MLS (Maximum Length
Sequence) signal, Pink noise and Sweep noise at setup-1 location. EASERA recorded the signals during each test
and provided the impulse response graphs, 3d waterfall graphs, clarity measurements (C7, C50, C80), arrival time,
EDT (Early Decay Time), articulation loss of consonants (Al cons), speech transmission index (STI, RaSTI) for each
case (Table 5.2-4). Values in dark green are acceptable values, values in light green are acceptable values, values in
yellow indicate fair and the values in red are unacceptable. Values in white cannot be classified as good or bad
values as they are relative to the acoustic setting and they help us in understanding the overall acoustic performance
at the data collection point.
190
LOG SWEEP MLS PINK NOISE SWEEP NOISE
C7 dB -5.3 -6.4 -4.2 -5
C50 dB 5.4 4.3 5.9 3.9
C80 dB 6.8 5.6 7.2 4.9
C35 dB 4.5 3.5 5 3.3
D 0.776 0.728 0.794 0.712
L7 dB SPL 72.6 75.2 83.5 78.8
L50 dB SPL 78 81.2 88.1 83.5
L80 dB SPL 78.2 81.5 88.4 83.7
L35 dB SPL 77.8 80.9 87.9 83.3
Ltotal dB SPL 79.1 82.5 89.1 85
Center time ms 57.34 86.3 53.73 196.73
ST1 dB 0.9 2.1 -0.3 -0.1
ST2 dB 1.9 3.1 0.7 1
Arrival Time ms 71.4 71.4 1.4 71.44
Split Time ms 35 35 35 35
EDT s 1.38 1.48 1.33 1.37
T10 s 1.88 1.88 1.9 1.73
T20 s 1.82 1.58 1.86 2.04
T30 s 1.8 1.37 1.87 1.91
AlCons % 3.258 3.448 3.127 3.223
STI 0.73 0.72 0.738 0.732
STI (Male) 0.736 0.725 0.745 0.741
STI (Female) 0.755 0.743 0.765 0.761
RaSTI 0.68 0.671 0.684 0.685
Equiv. STIPa (Male) 0.74 0.73 0.749 0.745
Equiv. STIPa
(Female)
0.753 0.742 0.764 0.759
Table 5.2-4 Harris Hall courtyard setup-2 field study results
EASE calculated the total, average, maximum and minimum SPL, C7, C50 and C80 at setup-1 location
(Table 5.2-5). Total SPL values are color scaled from 55 dB – 115 dB in red to green. Clarity values in dark green
are acceptable, values in light green are slightly out of range from acceptable range, values in yellow are fair and
values in red are unacceptable.
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EASE SIMULATION SETUP-2
Frequency Total SPL C7 (dB) C50 C80
Current Pos. Average Maximum Minimum
100 Hz
80.01 82.66 105.31 79.85 -5.17 6.9 12.01
125 Hz
79.98 82.64 105.31 79.82 -5.14 6.94 12.07
160 Hz
80.59 83.27 105.22 80.38 -4.75 7.1 12.23
200 Hz
81.22 83.91 105.14 80.95 -4.36 7.26 12.41
250 Hz
81.86 84.56 105.48 81.53 -3.98 7.43 12.59
315 Hz
81.32 84.21 104.42 80.85 -2.8 8.05 13.27
400 Hz
80.95 83.97 103.68 80.32 -1.7 8.72 14
500 Hz
80.74 83.83 103.12 79.94 -0.71 9.39 14.74
630 Hz
80.78 83.85 103.14 79.92 -0.16 9.71 15.06
800 Hz
80.88 83.91 103.24 79.98 0.29 10 15.36
1000 Hz
81.05 84.02 103.41 79.95 0.68 10.26 15.62
1250 Hz
81.51 84.44 104.47 80.12 0.54 10.29 15.71
1600 Hz
82.03 84.91 105.68 80.43 0.31 10.26 15.76
2000 Hz
82.63 85.43 107.87 80.92 -0.09 10.16 15.74
2500 Hz
81.67 84.19 105.43 78.92 1.13 10.96 16.56
3150 Hz
80.85 83.07 103.7 77.26 2.15 11.74 17.38
4000 Hz
80.13 82.02 102.25 75.84 3.01 12.48 18.2
5000 Hz
80.41 82.43 103.12 76.5 2.45 12.15 17.92
6300 Hz
80.62 82.79 104.03 77.13 1.8 11.89 17.78
8000 Hz
80.69 83.06 104.92 77.69 1.01 11.73 17.85
10000 Hz
80.01 82.66 105.31 79.85 -5.17 6.9 12.01
Table 5.2-5 Harris Hall courtyard setup-2 EASE simulation results
EASERA provided a wide range of data and graphs which were described in chapter 4. The data was
summarized to draw comparison from the EASE simulation results. Results show that the Clarity values are similar
to the field study measurements.
5.2.4 Revit and Dynamo
After the development of the Dynamo script for running the acoustic simulation on Revit models, the script
crashed due to the instability of the software, which could not handle the complex calculations associated with the
ray tracing algorithm. The results turned out to be similar even after trying several methods of simplifying the script
to perform the same set of calculations. It was concluded that the current version of Dynamo cannot handle the
complexity of the script. There were no results obtained from Dynamo script.
192
5.2.5 Conclusions from Harris Hall Courtyard
The main purpose of conducting the acoustic field study at Harris Hall courtyard was for its similarity to a
stadium space with similar spatial configuration (open to sky with enclosed on sides) on a smaller scale. The field
study was not conducted with the notion of analyzing the space and the speaker placement configurations and
evaluate the acoustic conditions. The primary intent was to develop a Dynamo script to calculate all the acoustical
parameters. The speaker systems were placed in the study to maximize reflections so that the acoustic parameters
can be calculated using Dynamo. It was first tested by comparing real data from measurements in Harris Hall
courtyard to the simulation. The acoustic simulation of the courtyard provided slightly higher sound levels results
than the acoustic field study data, which is probably due to the presence of trees in the courtyard that could not be
modeled in the EASE model. There was sufficient data to conduct a detailed analysis; however the focus of the
study is concentrated on the Los Angeles Memorial Coliseum and the retrofit study and the Harris Hall courtyard
data can be used as a ground work for developing and valuating the Dynamo, which is included in the possible
future study scope in chapter 7.
193
5.3 Los Angeles Memorial Coliseum
Los Angeles Memorial Coliseum was visited 7 times during the 2017-18 college football season. USC
Trojans played 7 home games at the Coliseum. The Extech HD 600 and Sound Analyzer app was used to record data
during the football game. Due to security reasons, advanced sound pressure level meters could not be taken inside
the stadium on game days. The Sound Analyzer app was installed on the mobile device and calibrated using Extech
HD 600 before collecting data in the Coliseum (Fig 4.3-1).
Figure 5.3-1 Los Angeles Memorial Coliseum methodology overview
Data was collected using Coliseum map showing the data collection points using Sound Analyzer mobile
application on Google Pixel mobile device. Los Angeles Memorial Coliseum was visited during the 2017 college
football season. The mobile application was used to collect sound pressure levels at 7 locations namely Student
section-1, Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans (Fig
5.3-2). Data was collected during various times during the game. Data was collected during various in game
scenarios (USC Touchdown, steal, turnover, 3
rd
down etc.) for a period of 20-40 seconds. All the data files from a
194
game are combined into a single spreadsheet and the peak, average and minimum sound pressure values are reported
for each location for all 7 home games (Fig 5.3-3).
Figure 5.3-2 Los Angeles Memorial Coliseum field study data collection points
Figure 5.3-3 Los Angeles Memorial Coliseum field study results overview
195
Los Angeles Memorial Coliseum was simulated in EASE. The results from EASE simulation are described
below. Two scenarios were considered while simulating the acoustic conditions of the Coliseum. The input for
ambient noise varied in both the scenarios which are taken from the field study data collected at the Coliseum during
the 2017 football season.
Scenario-1 data was collected during play. Scenario-2 input data was based on the peak noise levels
measured during in game scenarios (USC Trojans Touchdown, Sack etc.) favoring the home team which bring the
loudest response from the audience. Two sets of simulation results are described based on each scenario. The same
input data will be used for the EASE simulations of the design modification analysis of the Coliseum. Scenario-2
will have all the speaker sound pressure levels increased by 15 decibels. All mappings of the Coliseum shown in
results are based on 1000 Hz frequency (Fig 5.3-4). However, several listener seats were placed in the model similar
to the locations used for collecting data at the Coliseum (Fig 5.3-5). All listeners seats will have results from Octave
bandwidth range (100 Hz – 10000 Hz).
Figure 5.3-4 Los Angeles Memorial Coliseum EASE simulation results overview
196
Figure 5.3-5 Los Angeles Memorial Coliseum EASE simulation audience seat locations
5.3.1 Observations from the Field study
Conducting the field study during the college football season aided in understanding how the architecture
of the stadium, sound system design, in-game attendance, seating arrangement influence the overall acoustic
performance of the stadium. The findings have been described based on the results collected at each location and the
other observations which were instrumental in developing the EASE simulation model to develop the two retrofit
options.
Speaker location and Architecture of the Coliseum
The placement of speaker systems in the Los Angeles Memorial Coliseum played a major role in the
overall acoustic quality. The speaker systems were placed on the sides of the USC band, Titantron screen, and in
front of the audience at the west end of the field. The speaker system is not efficiently directed towards all sections
of the audience (Fig 5.3-6). The northwest and southwest corners of the stadium do not receive direct sound from
197
the speaker system. The cheerleaders are present in front of the student section to draw more excitement from the
student crowd. The student sections drew the loudest reaction and the highest SPL values during the field study.
The open bowl shape of the Coliseum does not help in retaining sound and directing towards the field. The
stands in the higher levels recorded lower SPL values. The proposed retrofit should incorporate a roof system to
retain the sound into the field.
Figure 5.3-6 Los Angeles Memorial Coliseum field study observations
Data collection shortcomings
An acoustic field study was conducted during the 2017-18 college football season at the Los Angeles
Memorial Coliseum. Sound Analyzer app was used to collect data using Google Pixel mobile device. Advanced
acoustic measurement equipment could not be used for measurement due to security reasons in the Coliseum. A
consistent acoustic measurement data could not be achieved due to the inconsistent attendance in the stadium
through the season. All the afternoon games had lower attendance due to the afternoon warm weather conditions in
198
southern California (Table 5.3-1). Also, the student sections saw many people leave in the second half of the
afternoon games due to the sunny weather conditions. Data could not be collected at different locations at the same
time which would have helped under the difference in SPL levels between the audience sections. Sound pressure
level measurements could not be conducted on the field due to security reasons. There was reduced attendance in the
Coliseum during the second half during the last quarter when USC Trojans were leading comfortably. Exceptions
were the games against Texas Longhorns which had the best in game atmosphere as the game went into extra time.
Similarly, the UCLA Bruins game had an intense atmosphere being the last game of the season.
S.No Date Start
of play (PT)
Opponent Home/Away Final
score
Attendance
1. 09/02/2017 02:15 PM Western Michigan Home 49-31 61125
2. 09/09/2017 05:30 PM Stanford Cardinals Home 42-24 77614
3. 09/16/2017 05:30 PM Texas Longhorns Home 27-24 84714
4. 09/23/2017 12:30 PM California Golden Bears Away 30-20 46747
5. 09/29/2017 07:30 PM Washington State Away 27-30 33773
6. 10/07/2017 01:00 PM Oregon State Beavers Home 38-10 60314
7. 10/14/2017 05:00 PM Utah Utes Home 28-27 72382
8. 10/21/2017 04:30 PM Notre Dame Away 14-49 77622
9. 01/28/2017 07:45 PM Arizona State Away 48-17 53446
10. 11/04/2017 07:45 PM Arizona Wildcats Home 49-35 70225
11. 11/11/2017 01:00 PM Colorado Away 38-24 49337
12. 11/18/2017 05:00 PM UCLA Bruins Home 28-23 82407
Table 5.3-1 USC Trojans college football 2017-18 season schedule and results (University of Southern California Athletics,
2018)
Total SPL at various locations
Field study data collected at the Coliseum was organized bases on each location namely Student section-1,
Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans for all the
games to draw a comparison on the total sound pressure levels at the Coliseum.
Student section-1
Peak and minimum values at the Student section-1 from Coliseum field study was tabulated from the
results (Table 5.3-2) (Table 5.3-3). Results showed that the game against Texas Longhorns and the UCLA bruins
recorded the highest sound pressure values due to the higher stadium attendance. Both the games were played in the
evening which had the larger crowd stay till the end of the game. The Texas game went into extra time and had more
exciting moments which had an influence on the SPL values. Given the rivalry between USC Trojans and UCLA
199
Bruins, the game had more excitement among the audience and it was the last game of the season which resulted in
higher SPL noises in the audience stands. The game against Western Michigan despite being the season opener had
a very low attendance due to the early kick off time (02:15 PM). Similarly, the Oregon State Beavers game also had
similar attendance due to the early kick off time (01:00 PM). The student section-1 had the highest SPL values
recorded of all the data collection points which can be attributed to the students with the USC band and the
cheerleaders closer to the student section (Fig 5.3-7).
Opponent
Attendance in
Stadium
Kick off
time
63 Hz
(dB)
125
Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz
(dB)
2000
Hz
(dB)
4000
Hz
(dB)
8000
Hz
(dB)
Global
(dB)
Texas Longhorns 84714 5:30 PM 38.18 43.09 68.95 88.61 95.04 79.45 70.27 71.23 99.31
UCLA Bruins 82407 5:00 PM 46.4 57.06 68.77 80.29 91.67 81.39 70.28 69.18 99.1
Arizona Wildcats 70225 7:45 PM 38.07 44.01 68.5 86.54 89.42 80.05 69.58 68.41 98.82
Utah Utes 72382 5:00 PM 42.6 47.75 69.05 81.65 90.36 86.85 75.42 72.73 97.18
Western Michigan 61125 2:15 PM 42.73 47.55 69.21 82.15 88.38 83.92 74.21 66.75 96.01
Oregon State Beavers 60314 1:00 PM 40.19 46.43 71.15 84.81 85.6 83.6 70.46 72.08 95.38
Stanford Cardinals 77614 5:30 PM 47.62 58.24 82.12 80.57 85.45 85.16 70.82 66.98 94.68
Table 5.3-2 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at student section-1
Opponent
Attendance in
Stadium
Kick off
time
63 Hz
(dB)
125
Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz
(dB)
2000
Hz
(dB)
4000
Hz
(dB)
8000
Hz
(dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 37.39 49.25 66.53 73.93 79.5 71.4 68.83 58.54 81.48
Texas Longhorns 84714 5:30 PM 31.49 52.02 55.56 64.63 73.97 72.63 62.5 63.67 77.06
Arizona Wildcats 70225 7:45 PM 35.05 51.3 58.93 62.69 73.11 74.08 58.74 56.54 76.99
Utah Utes 72382 5:00 PM 36.03 50.64 60.39 66.41 72.54 73.66 64.76 53.56 76.99
Western Michigan 61125 2:15 PM 26.94 49.07 57.69 65.38 72.35 73.74 66.05 58.3 76.96
Oregon State Beavers 60314 1:00 PM 35.72 50.79 57.91 67.74 74.29 71.39 62.79 54.57 76.95
Stanford Cardinals 77614 5:30 PM 32.92 51.56 59.31 63.91 70.15 74.97 64.32 54.77 76.83
Table 5.3-3 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at student section-1
200
Figure 5.3-7 Los Angeles Memorial Coliseum view from Student section-1
Student section-2
Peak and minimum values at the Student section-2 from Coliseum field study was tabulated from the
results (Table 5.3-4) (Table 5.3-5). Results showed that the game against Texas Longhorns and the UCLA bruins
recorded the highest sound pressure values due to the higher stadium attendance. Both the games were played in the
evening which had the larger crowd stay till the end of the game. The Texas game went into extra time and had more
exciting moments which had an influence on the SPL values. Given the rivalry between USC Trojans and UCLA
Bruins, the game had more excitement among the audience and it was the last game of the season which resulted in
higher SPL noises in the audience stands. The game against Western Michigan despite being the season opener had
a very low attendance due to the early kick off time (02:15 PM) on a summer afternoon. Similarly, the Oregon State
Beavers game also had similar attendance due to the early kick off time (01:00 PM). The student section-1 had the
highest SPL values recorded of all the data collection points which can be attributed to the students with the USC
band and the cheerleaders closer to the student section (Fig 5.3-8).
201
Opponent
Attendance in
Stadium
Kick off
time
63 Hz
(dB)
125
Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz
(dB)
2000
Hz
(dB)
4000
Hz
(dB)
8000
Hz
(dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 55.09 55.28 70.18 80.85 85.09 84.25 73.14 70.43 95.27
Arizona Wildcats 70225 7:45 PM 54.38 59.42 79.34 80.38 83.46 86.87 72.32 73.3 94.4
Texas Longhorns 84714 5:30 PM 57.02 56.43 71.04 81.42 86.67 83.49 72.2 70.99 94.31
Utah 72382 5:00 PM 47.44 50.08 66.97 77.21 87.24 77.55 63.41 57.07 92.2
Western Michigan 61125 2:15 PM 46.73 50.9 65.27 78.14 82.84 79.71 71.91 60.06 91.85
Stanford Cardinals 77614 5:30 PM 40.45 48.27 66.16 81.13 79.68 75.76 66.51 60.22 89.82
Oregon State Beavers 60314 1:00 PM 41.3 50.88 62.96 77.88 78.32 76.1 60.27 57.32 88.36
Table 5.3-4 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at student section-2
Opponent
Attendance in
Stadium
Kick off
time
63 Hz
(dB)
125
Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz
(dB)
2000
Hz
(dB)
4000
Hz
(dB)
8000
Hz
(dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 27.12 38.07 48.54 59.51 62.78 61.13 51.61 56.49 66.77
Texas Longhorns 84714 5:30 PM 27.7 37.19 50.22 59.81 63.31 60.38 51.84 54.2 66.74
Arizona Wildcats 70225 7:45 PM 25.91 35.12 48.93 59.83 63.53 59.96 51.42 52.76 66.64
Oregon State Beavers 60314 1:00 PM 29.77 41.12 48.5 54.33 54.67 56.02 46.66 42.02 66.5
Utah Utes 72382 5:00 PM 32.03 40.3 48.51 54.74 56.84 56.15 46.14 42.62 66.49
Western Michigan 61125 2:15 PM 32.55 40.83 51.01 56.41 55.5 55 45.93 39.89 66.22
Stanford Cardinals 77614 5:30 PM 32.49 42.48 50.37 56.65 55.71 54.89 45.1 40.14 65.87
Table 5.3-5 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at student section-2
Figure 5.3-8 Los Angeles Memorial Coliseum view from Student section-2
202
Northwest corner
Peak and minimum values at the Northwest corner from Coliseum field study was tabulated from the
results (Table 5.3-6) (Table 5.3-7). Results showed that the game against Texas Longhorns and the UCLA bruins
recorded the highest sound pressure values due to the higher stadium attendance. Both the games were played in the
evening which had the larger crowd stay till the end of the game. The Texas game went into extra time and had more
exciting moments which had an influence on the SPL values. Given the rivalry between USC Trojans and UCLA
Bruins, the game had more excitement among the audience and it was the last game of the season which resulted in
higher SPL noises in the audience stands. The game against Western Michigan despite being the season opener had
a very low attendance due to the early kick off time (02:15 PM) on a summer afternoon. Similarly, the Oregon State
Beavers game also had similar attendance due to the early kick off time (01:00 PM). Northwest corner had relatively
lower SPL values recorded as it is in the acoustic shadow part of the Coliseum where the direct rays of the speaker
system and the audience noise fail to reach. North west corner and the southwest corners of the stadium have the
same condition which were reflected in their relatively lower SPL values which is taken into consideration while
designing the retrofit (Fig 5.3-9).
Opponent
Attendance
in Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500
Hz
(dB)
1000 Hz
(dB)
2000
Hz
(dB)
4000 Hz
(dB)
8000 Hz
(dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 48.3 59.46 68.14 75.26 84.78 83.39 77.65 70.77 87.99
Texas Longhorns 84714 5:30 PM 39.94 53.22 66.8 74.05 82.85 74.38 66.03 57.67 84.07
Arizona Wildcats 70225 7:45 PM 39.46 52.26 67.1 75.02 80.9 73.44 66.56 58.74 82.73
Stanford Cardinals 77614 5:30 PM 40.28 50.58 65.41 74.47 78.94 74.34 68.55 56.9 81.61
Western Michigan 61125 2:15 PM 43.19 55.08 68.66 73.84 78.68 73.13 64.89 57.38 81.13
Utah 72382 5:00 PM 39.57 53.09 66.83 74.13 76.5 75.12 72.83 57.91 81.07
Oregon State Beavers 60314 1:00 PM 40.21 51.4 67.46 75.46 76.97 72.88 67.41 59.09 80.66
Table 5.3-6 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at northwest corner
203
Opponent
Attendance
in Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz
(dB)
2000
Hz
(dB)
4000
Hz
(dB)
8000
Hz
(dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 22.99 33.62 48.49 63.43 64.16 63.18 60.74 51.49 69.18
Texas Longhorns 84714 5:30 PM 22.29 38.51 51.51 62.27 64.04 65.24 55.39 52.66 69.16
Arizona Wildcats 70225 7:45 PM 20.1 35.36 49.25 61.45 65.34 64.35 55.72 52.59 69.13
Utah Utes 72382 5:00 PM 30.32 46.82 53.63 61.27 64.22 65.21 55.27 53.45 69.11
Western Michigan 61125 2:15 PM 22.76 34.23 46.85 59.39 65.45 64.55 58.47 51.68 69.1
Oregon State Beavers 60314 1:00 PM 19.59 33.25 49.49 62.91 64.96 63.13 58.44 50.84 69.06
Stanford Cardinals 77614 5:30 PM 21.39 32.99 47.54 63.13 64.35 64.35 54.07 52.8 69.03
Table 5.3-7 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at northwest corner
Figure 5.3-9 Los Angeles Memorial Coliseum view from Northwest corner
General public-1
Peak and minimum values at the General public-1 from Coliseum field study was tabulated from the results
(Table 5.3-8) (Table 5.3-9). Results showed that the game against Texas Longhorns and the UCLA bruins recorded
the highest sound pressure values due to the higher stadium attendance. Both the games were played in the evening
which had the larger crowd stay till the end of the game. The Texas game went into extra time and had more
exciting moments which had an influence on the SPL values. Given the rivalry between USC Trojans and UCLA
Bruins, the game had more excitement among the audience and it was the last game of the season which resulted in
204
higher SPL noises in the audience stands. The game against Western Michigan despite being the season opener had
a very low attendance due to the early kick off time (02:15 PM) on a summer afternoon. Similarly, the Oregon State
Beavers game also had similar attendance due to the early kick off time (01:00 PM). General public-1 recorded SPL
values higher than the Northwest corner due to the direct sound from the Titantron speakers and the speaker system
in front of the cheerleaders on the west end of the field (Fig 5.3-10).
Opponent
Attendance in
Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz (dB)
2000
Hz (dB)
4000
Hz (dB)
8000
Hz (dB)
Global
(dB)
Texas Longhorns 84714 5:30 PM 25.11 45.24 64.99 74.7 79.65 79.62 66.45 59.14 83.46
UCLA Bruins 82407 5:00 PM 38.96 53.31 66.64 74.62 81.9 73.98 65.96 58.41 83.39
Arizona Wildcats 70225 7:45 PM 23.31 43.82 61.36 73.78 81.57 73.78 63.18 56.28 82.91
Utah 72382 5:00 PM 41.78 54.09 66.54 74.05 75.63 72.65 69.65 59.01 79.79
Oregon State Beavers 60314 1:00 PM 23.28 45.03 59.12 73.74 75.2 71.71 62.53 58.85 78.75
Western Michigan 61125 2:15 PM 24.1 43.34 58.26 69.38 74.14 72.22 60.11 57.79 77.29
Stanford Cardinals 77614 5:30 PM 23.22 44.47 59.68 70.73 72.84 70.98 60.73 60.45 76.71
Table 5.3-8 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at general public-1
Opponent
Attendance in
Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz (dB)
2000
Hz (dB)
4000
Hz (dB)
8000
Hz (dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 22.37 37.5 50.8 61.61 68.75 65.35 55.19 51.15 71.13
Texas Longhorns 84714 5:30 PM 35.95 50.2 57.68 64.6 67.21 65.53 54.31 50.57 71.07
Arizona Wildcats 70225 7:45 PM 38.25 52.01 58.95 63.18 66.8 66.5 55.75 50.94 71.06
Utah Utes 72382 5:00 PM 37.08 52.84 56.36 64.43 67.11 65.69 54.43 51.29 71.02
Western Michigan 61125 2:15 PM 24.62 35.4 47.96 60.47 69.51 63.05 54.51 50.73 70.98
Oregon State Beavers 60314 1:00 PM 22.11 36.15 50.61 62.25 68.69 64.61 54.27 50.9 70.96
Stanford Cardinals 77614 5:30 PM 20.62 34.98 51.65 65.71 66.76 65.2 55.44 51.88 70.94
Table 5.3-9 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at general public-1
Figure 5.3-10 Los Angeles Memorial Coliseum view from General public-1
205
Titantron-1
Peak and minimum values at the Titantron-1 from Coliseum field study was tabulated from the results
(Table 5.3-10) (Table 5.3-11). Results showed that the game against Texas Longhorns and the UCLA bruins
recorded the highest sound pressure values due to the higher stadium attendance. Both the games were played in the
evening which had the larger crowd stay till the end of the game. The Texas game went into extra time and had more
exciting moments which had an influence on the SPL values. Given the rivalry between USC Trojans and UCLA
Bruins, the game had more excitement among the audience and it was the last game of the season which resulted in
higher SPL noises in the audience stands. The game against Western Michigan despite being the season opener had
a very low attendance due to the early kick off time (02:15 PM) on a summer afternoon. Similarly, the Oregon State
Beavers game also had similar attendance due to the early kick off time (01:00 PM). Titantron-1 results were
influenced by the two sets of speakers from the Titantron and the speakers on the field directed towards the
audience. Titantron recorded the highest SPL values after the student sections (Fig 5.3-11).
Opponent
Attendance in
Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz (dB)
2000
Hz (dB)
4000
Hz (dB)
8000
Hz (dB)
Global
(dB)
Texas Longhorns 84714 5:30 PM 48.36 48.18 63.35 79.19 82.77 79.02 64.88 55.44 90.6
UCLA Bruins 82407 5:00 PM 44.25 53.68 68.85 76.81 81.25 88.75 81.12 73.58 90.38
Arizona Wildcats 70225 7:45 PM 48.84 57.94 69.2 75.57 88.27 84.04 76.97 73.01 90.17
Utah 72382 5:00 PM 42.18 49.5 67.84 76.62 82.19 88.18 79.54 75.18 89.99
Western Michigan 61125 2:15 PM 48.57 60.34 68.04 75.43 88.62 81.74 76.78 73.21 89.95
Stanford Cardinals 77614 5:30 PM 44.74 51.27 65.74 77.8 83.18 84.02 75.92 71.05 87.6
Oregon State Beavers 60314 1:00 PM 47.52 58.75 66.8 75.69 83.09 81.1 75.8 77.12 86.67
Table 5.3-10 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at Titantron
Opponent
Attendance
in Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz (dB)
2000
Hz (dB)
4000
Hz (dB)
8000
Hz (dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 35.14 48.97 53.65 66.69 72.64 65.49 61.49 55.55 74.57
Texas Longhorns 84714 5:30 PM 35.24 49.69 59.95 63.87 68.13 72.16 62.17 56.14 74.55
Arizona Wildcats 70225 7:45 PM 25.48 36.3 52.7 67.09 71.52 68.73 57.12 56.19 74.45
Utah Utes 72382 5:00 PM 37.19 48.76 54.67 67.5 71.25 66.94 59.24 56.59 74.08
Western Michigan 61125 2:15 PM 35.49 52.51 59.37 63.45 69.42 70.8 59.69 51.68 74
Oregon State Beavers 60314 1:00 PM 36.93 53.45 59.49 62.11 70.71 69.13 60.98 54.82 73.85
Stanford Cardinals 77614 5:30 PM 32.72 46.86 55.58 64.27 70.42 69.37 57.49 54.96 73.73
Table 5.3-11 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at Titantron
206
Figure 5.3-11 Los Angeles Memorial Coliseum view from the Titantron
General Public-2
Peak and minimum values at the General public-2 from Coliseum field study was tabulated from the results
(Table 5.3-11) (Table 5.3-12). Results showed that the game against Texas Longhorns and the UCLA Bruins
recorded the highest sound pressure values due to the higher stadium attendance. Both the games were played in the
evening which had the larger crowd stay till the end of the game. The Texas game went into extra time and had more
exciting moments which had an influence on the SPL values. Given the rivalry between USC Trojans and UCLA
Bruins, the game had more excitement among the audience and it was the last game of the season which resulted in
higher SPL noises in the audience stands. The game against Western Michigan despite being the season opener had
a very low attendance due to the early kick off time (02:15 PM) on a summer afternoon. Similarly, the Oregon State
Beavers game also had similar attendance due to the early kick off time (01:00 PM). General public-2 data was in
the south western part of the Coliseum which had similar acoustic condition to the northwest corner. General public-
2 recorded valued higher than the northwest corner due to its location in the middle stands (Fig 5.3-12).
207
Opponent
Attendance
in Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz (dB)
2000
Hz (dB)
4000
Hz (dB)
8000
Hz (dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM
23.43 42.76 62.56 74.33 80.46 80.24 66 59.05 83.99
Arizona Wildcats 70225 7:45 PM
39.46 52.26 67.1 75.02 80.9 73.44 66.56 58.74 82.73
Texas Longhorns 84714 5:30 PM
45.04 54.68 66.73 72.99 80.82 74.38 66.75 58.21 82.52
Western Michigan 61125 2:15 PM
39.57 53.09 66.83 74.13 76.5 75.12 72.83 57.91 81.07
Utah 72382 5:00 PM
39.89 51.86 71.32 75.16 76.62 72.48 65.87 60.82 80.62
Oregon State Beavers 60314 1:00 PM
31.43 46.29 71.12 73.89 75.6 71.31 68.13 56.99 79.75
Stanford Cardinals 77614 5:30 PM
42.98 54.57 65.74 74.82 75.86 71.35 65.77 57 79.59
Table 5.3-12 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at general public-2
Opponent
Attendance
in Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz (dB)
2000
Hz (dB)
4000
Hz (dB)
8000
Hz (dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 27.8 39.61 48.96 57.61 58.8 56.82 47.91 46.02 68.69
Texas Longhorns 84714 5:30 PM 31.29 39.78 48.37 57.73 56.31 56.11 46.69 43.72 67.2
Arizona Wildcats 70225 7:45 PM 28.33 42.51 52.09 56.44 53.81 55.34 47.72 42.18 66.63
Utah Utes 72382 5:00 PM 32.74 40.44 47.29 54.74 56.37 55.92 46.82 43.96 66.42
Oregon State Beavers 60314 1:00 PM 33.07 39.21 48.82 56.85 54.54 54.97 45.6 39.6 66.12
Western Michigan 61125 2:15 PM 31.99 41.64 46.44 54.44 55.24 55.39 46.49 43.67 65.99
Stanford Cardinals 77614 5:30 PM 32.11 41.18 47.82 55.76 54.07 55.1 44.81 41.19 65.41
Table 5.3-13 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at general public-2
Figure 5.3-12 Los Angeles Memorial Coliseum view from General public-2
208
Away fans
Peak and minimum values at the away fans from Coliseum field study was tabulated from the results
(Table 5.3-14) (Table 5.3-15). Results showed that the game against Texas Longhorns and the UCLA bruins
recorded the highest sound pressure values due to the higher stadium attendance. Both the games were played in the
evening which had the larger crowd stay till the end of the game. The Texas game went into extra time and had more
exciting moments which had an influence on the SPL values. Given the rivalry between USC Trojans and UCLA
Bruins, the game had more excitement among the audience and it was the last game of the season which resulted in
higher SPL noises in the audience stands. The game against Western Michigan despite being the season opener had
a very low attendance due to the early kick off time (02:15 PM) on a summer afternoon. Similarly, the Oregon State
Beavers game also had similar attendance due to the early kick off time (01:00 PM). Away fan stands were in the
southern stands in front of the Press box (Fig 5.3-13). They speakers from the band are located on the right side of
the away fans stand.
Opponent
Attendance
in Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000
Hz (dB)
2000
Hz (dB)
4000
Hz (dB)
8000
Hz (dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 13.7 28.13 47.15 61.47 80.05 68.54 61.15 55.01 85.02
Arizona Wildcats 70225 7:45 PM 28.04 38.27 62.11 66.17 71.3 69.77 62.19 52.27 84.8
Texas Longhorns 84714 5:30 PM 28.81 40 62.65 66.44 72.69 71.59 62.71 53.66 83.89
Utah 72382 5:00 PM 36.3 50.24 65.27 74.35 79.48 75.54 72.43 58.55 82.39
Western Michigan 61125 2:15 PM 44.59 54.45 67.38 73.49 79.14 72.94 65.53 58.26 81.28
Oregon State Beavers 60314 1:00 PM 35.44 48.67 65.45 74.08 76.41 73.03 69.14 55.49 80.07
Stanford Cardinals 77614 5:30 PM 42.76 53.47 68.84 74.21 76.12 71.6 69.7 58.35 79.99
Table 5.3-14 Los Angeles Memorial Coliseum field study Total SPL peak value comparison at away fans
Opponent
Attendance
in Stadium
Kick off
time
63 Hz
(dB)
125 Hz
(dB)
250 Hz
(dB)
500 Hz
(dB)
1000 Hz
(dB)
2000 Hz
(dB)
4000 Hz
(dB)
8000 Hz
(dB)
Global
(dB)
UCLA Bruins 82407 5:00 PM 26.44 46.68 54.33 64 66.3 68.9 57.76 52.24 72.13
Texas Longhorns 84714 5:30 PM 35.4 52.24 56.74 64.48 68.3 66.56 57.46 53.11 71.9
Western Michigan 61125 2:15 PM 21.05 34.07 49.38 65.25 69.09 65.11 55.09 52.55 71.85
Arizona Wildcats 70225 7:45 PM 27.74 36.82 50.27 63.07 70.28 63.75 53.26 47.89 71.77
Utah Utes 72382 5:00 PM 27.14 44.99 52.32 63.67 67.39 68.28 55.97 52.15 71.48
Oregon State Beavers 60314 1:00 PM 36.31 49.35 58.35 64.7 67.67 66.84 56.55 54.1 70.27
Stanford Cardinals 77614 5:30 PM 35.99 49.97 58 65.71 68.34 65.3 54.31 50.09 69.89
Table 5.3-15 Los Angeles Memorial Coliseum field study Total SPL minimum value comparison at away fans
209
Figure 5.3-13 Los Angeles Memorial Coliseum view from the away fans
Total SPL takeaways
Data collection from the field study at the Los Angeles Memorial Coliseum showed that the Total SPL
values recorded are not as high as it should be for a stadium with a capacity of 93,500 (Fig 5.3-14). Results showed
that the game against Texas Longhorns and the UCLA bruins recorded the highest sound pressure values due to the
higher stadium attendance. Both the games were played in the evening which had the larger crowd stay till the end
of the game. The Texas game went into extra time and had more exciting moments which had an influence on the
SPL values. Given the rivalry between USC Trojans and UCLA Bruins, the game had more excitement among the
audience and it was the last game of the season which resulted in higher SPL noises in the audience stands. The
game against Western Michigan despite being the season opener had a very low attendance due to the early kick off
time (02:15 PM) on a summer afternoon. Similarly, the Oregon State Beavers game also had similar attendance due
to the early kick off time (01:00 PM). Highest recorded value was 99.31 dB at the student section-1 and lowest
recorded value was 65.87 dB at the student section-2. Major reason for such lower SPL values is the absence of a
roof system which would help reflect the noise towards the field and to other audience stands which in turn would
make the audience cheer even more thereby increasing the overall SPL levels in the stadium. Also, the distribution
of the speaker systems is found to be inefficient as it does not reach the farther stands in the stadium. A retrofit with
a roof and a reconfigured sound system could improve the acoustic performance of the stadium.
210
Figure 5.3-14 Los Angeles Memorial Coliseum field study overall peak and minimum Total SPL at listeners seats
Takeaways for developing the EASE simulation model and the retrofit
The curvilinear surfaces were simplified into planar polygons to reduce the complexity of the geometry. It
was decided to model the base geometry in AutoCAD 3d and export it to Sketchup. The DWG file was then opened
in Sketchup to eliminate the unnecessary surfaces and reduce simulation time. All the surfaces that did not receive
any reflections were eliminated to expedite the computing process during simulations. EASE detects layers from
Sketchup model to apply materials on the model. A partial roof system can be added over the northern and southern
stands to reflect the sound towards the field. The existing speaker system can be reconfigured to distribute equally
towards all the audience stands to improve overall acoustic quality.
211
5.3.2 Acoustic software simulation - EASE
Los Angeles Memorial Coliseum was simulated in EASE. The results from EASE simulation are described
below. Two scenarios were considered while simulating the acoustic conditions of the Coliseum. The input for
ambient noise varied in both the scenarios which are taken from the field study data collected at the Coliseum during
the 2017 football season.
Scenario-1 data was collected during play. Scenario-2 input data was based on the peak noise levels
measured during in game scenarios (USC Trojans Touchdown, Sack etc.) favoring the home team which bring the
loudest response from the audience (Table 5.3-15). Two sets of simulation results are described based on each
scenario. The same input data will be used for the EASE simulations of the design modification analysis of the
Coliseum. Scenario-2 will have all the speaker sound pressure levels increased by 15 decibels. All mappings of the
Coliseum shown in results are based on 1000 Hz frequency (Fig 5.3-15). However, several listener seats were
placed in the model similar to the locations used for collecting data at the Coliseum. All listeners’ seats will have
results from Octave bandwidth range (100 Hz – 10000 Hz).
Figure 5.3-15 Los Angeles Memorial Coliseum EASE simulation results overview
212
Figure 5.3-16 Los Angeles Memorial Coliseum EASE simulation audience seat locations
Frequency Scenario-1 (dB) Scenario-2 (dB)
100 Hz 40.44 55.44
125 Hz 45.99 60.99
160 Hz 54.86 69.86
200 Hz 67.06 82.06
250 Hz 65.43 80.43
315 Hz 68.83 83.83
400 Hz 68.83 83.83
500 Hz 72.37 87.37
630 Hz 81.52 96.52
800 Hz 79.59 94.59
1 kHz 77.88 92.88
1.25 kHz 81.97 96.97
1.6 kHz 81.50 96.50
2 kHz 80.33 95.33
2.5 kHz 73.84 88.84
3.15 kHz 68.11 83.11
4 kHz 62.36 77.36
5 kHz 68.06 83.06
6.3 kHz 73.96 88.96
8 kHz 79.08 94.08
10 kHz 72.07 87.07
Table 5.3-16 Los Angeles Memorial Coliseum EASE simulation input data
213
Total sound pressure level (SPL)
Total sound pressure level (SPL) at the Coliseum mapping at 1000 Hz for scenario-1 was simulated in EASE (Fig
5.3-16). The overall sound pressure levels at each location of the Coliseum can be interpreted from the mapping.
Color scaled mapping can be useful to interpret uneven distribution of sound and speaker system throughout the
space. EASE calculated the sound pressure levels at 7 locations namely Student section-1, Student section-2,
General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation
are exported as a table with the overall peak, average and minimum sound pressure values with the sound pressure
levels for each location (Table 5.3-17).
Scenario-1 calculated the Total SPL at lower ambient noise level. The mapping shows the SPL levels are
higher at the audience stands closer to the speaker systems. The placement of speaker systems played a critical role
in overall SPL values. EASE simulation mapping showed the audience stands closer to the speaker systems had a
higher SPL values which was similar to the field study observations. Possible reason for this was the absence of a
roof system which would have reflected the sound towards the audience stands and fieldfield.
Figure 5.3-17 Los Angeles Memorial Coliseum EASE simulation scenario-1 Total SPL at 1000 Hz mapping
214
FREQUENCY
MAXIMUM
(dBA)
MINIMUM
(dBA)
AVERAGE
(dBA)
STUDENT
SECTION-1
(dBA)
STUDENT
SECTION-2
(dBA)
GENERAL
PUBLIC-1
(dBA)
GENERAL
PUBLIC-2
(dBA)
TITANTRON-1
(dBA)
TITANTRON-2
(dBA)
SOUTHWEST
CORNER (dBA)
PRESS BOX-1
(dBA)
100 Hz 57.11 58.4 57.32 56.79 57.33 57.16 58.24 56.81 56.85 57.11 58.4
125 Hz 61.06 62.57 61.34 60.7 61.35 61.13 62.37 60.72 60.77 61.06 62.57
160 Hz 62.79 64.82 63.25 62.33 63.19 62.85 64.36 62.37 62.43 62.79 64.82
200 Hz 64.25 66.87 64.94 63.67 64.68 64.2 65.82 63.7 63.84 64.25 66.87
250 Hz 66.92 70.25 67.89 66.2 67.7 66.94 69.07 66.29 66.41 66.92 70.25
315 Hz 66.82 70.82 68.11 66.04 67.61 66.84 68.96 66.12 66.28 66.82 70.82
400 Hz 68.76 73.11 70.23 67.96 69.58 68.75 70.93 68.01 68.24 68.76 73.11
500 Hz 72.22 76.65 73.91 71.28 73.96 72.1 75.82 71.42 71.64 72.22 76.65
630 Hz 71.84 77.46 74.26 70.71 74.33 72.23 75.92 70.75 71.09 71.84 77.46
800 Hz 69.73 76.74 73.48 68.53 71.52 69.82 72.03 68.26 69.4 69.73 76.74
1000 Hz 70.09 77.6 74.85 68.75 70.92 69.87 71.82 68.81 70.4 70.09 77.6
1250 Hz 69.9 76.88 73.8 68.52 71.89 69.57 73.01 68.34 69.78 69.9 76.88
1600 Hz 70.88 77.93 74.88 69.52 73 70.47 73.5 69.05 70.73 70.88 77.93
2000 Hz 71.88 79.25 76.19 70.68 73.64 71.89 73.99 69.65 71.8 71.88 79.25
2500 Hz 70.27 78.34 74.42 69.03 71.48 70.17 72.33 68.3 69.94 70.27 78.34
3150 Hz 69.52 78.41 73.7 68.28 70.41 69.74 71.4 67.16 69.06 69.52 78.41
4000 Hz 66.98 75.89 71.75 65.64 67.64 67.21 68.22 64.49 66.84 66.98 75.89
5000 Hz 65.96 74.66 71.05 64.49 66.46 65.95 67.03 63.48 65.92 65.96 74.66
6300 Hz 64.42 73.51 69.69 62.49 65.51 64.06 65.45 62.11 64.49 64.42 73.51
8000 Hz 61.93 70.9 67.41 59.81 63.77 61.06 62.95 59.9 62.04 61.93 70.9
10000 Hz 59.64 67.64 63.4 57.95 63.08 58.54 61.86 58.13 59.16 59.64 67.64
Table 5.3-17 Los Angeles Memorial Coliseum EASE simulation scenario-1 total SPL at listeners seats
Total sound pressure level (SPL) at the Coliseum mapping at 1000 Hz for scenario-2 was simulated in
EASE (Fig 5.3-17). The overall sound pressure levels at each location of the Coliseum can be interpreted from the
mapping. Color scaled mapping can be useful to interpret uneven distribution of sound and speaker system
throughout the space. EASE calculated the sound pressure levels at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum sound pressure values with the sound
pressure levels for each location (Table 5.3-18).
Scenario-2 had an increased ambient noise which was used as an input from the field study at the Coliseum.
The speaker systems SPL levels were increased to their maximum value to simulate a scenario which would create a
noisier response among the audience (USC touchdown, interception, sack etc.). Highest value calculated by EASE
was 114 dB at the edge of the student section area closer to the USC band’s speaker system. The values calculated at
215
the audience seat locations by EASE simulations were slightly higher by 2-3 dB than the field study results which
can be negligible compared to the scale of the space.
EASE simulation results follow the similar pattern to the field study results where the locations closer to
the speaker systems record higher values and the higher located stands recorded lower SPL values. EASE
simulation results showed that the speaker systems are inefficiently distributed in the stadium which also is a major
reason for the difference in the SPL levels of various audience stands. The open bowl shape of the Coliseum does
not help in retaining sound and directing towards the field. The stands in the higher levels recorded lower SPL
values. Adding a roof system would help retain the sound inside the stadium and reflect it towards the audience
which in turn will liven up the atmosphere.
Figure 5.3-18 Los Angeles Memorial Coliseum EASE simulation scenario-2 Total SPL at 1000 Hz mapping
216
FREQUENCY
MAXIMUM
(dBA)
MINIMUM
(dBA)
AVERAGE
(dBA)
STUDENT
SECTION-1
(dBA)
STUDENT
SECTION-2
(dBA)
GENERAL
PUBLIC-1
(dBA)
GENERAL
PUBLIC-2
(dBA)
TITANTRON-1
(dBA)
TITANTRON-2
(dBA)
SOUTHWEST
CORNER (dBA)
PRESS BOX-1
(dBA)
100 Hz 98.6 84.31 84.93 85.85 85 84.65 85.34 85.14 86.4 84.71 84.71
125 Hz 103.08 88.17 88.89 89.97 88.99 88.56 89.38 89.12 90.56 88.64 88.64
160 Hz 105.12 89.65 90.61 92.08 90.81 90.19 91.26 90.88 92.61 90.31 90.33
200 Hz 107.08 90.82 92.06 94.06 92.41 91.52 92.79 92.25 94.1 91.66 91.76
250 Hz 110.09 93.19 94.72 97.44 95.26 94.01 95.9 95.04 97.44 94.28 94.37
315 Hz 109.07 92.75 94.6 97.85 95.33 93.84 95.83 94.97 97.35 94.15 94.26
400 Hz 108.76 94.57 96.53 100.08 97.36 95.76 97.81 96.88 99.32 96.03 96.24
500 Hz 113.13 97.77 99.99 103.67 100.99 99.04 102.31 100.24 104.34 99.48 99.71
630 Hz 112.41 96.25 99.59 104.77 101.35 98.26 102.79 100.53 104.49 98.92 99.32
800 Hz 111.5 92.85 97.45 104.23 100.4 95.76 99.93 98.14 100.55 96.51 97.8
1000 Hz 110.92 92.64 97.76 104.76 101.45 95.82 99.24 98.16 100.31 97.1 98.88
1250 Hz 110.49 93.37 97.6 104.01 100.42 95.82 100.33 97.84 101.57 96.55 98.16
1600 Hz 112.71 94.31 98.6 105.28 101.58 96.8 101.45 98.74 102.05 97.25 99.13
2000 Hz 114.19 94.78 99.59 107.05 103.06 97.73 102.08 100.26 102.53 97.87 100.24
2500 Hz 113.39 93.32 97.97 106.04 101.19 96.06 99.9 98.54 100.87 96.52 98.37
3150 Hz 113.44 92.51 97.23 106.31 100.6 95.2 98.82 98.15 99.94 95.38 97.48
4000 Hz 110.97 90.06 94.69 104.02 98.73 92.59 96.03 95.63 96.73 92.69 95.29
5000 Hz 110.34 89.37 93.68 102.8 98.17 91.54 94.86 94.36 95.52 91.65 94.35
6300 Hz 109.19 88.61 92.17 101.53 96.58 89.86 93.94 92.39 93.91 90.21 92.87
8000 Hz 107.5 86.81 89.72 98.96 94.23 87.45 92.24 89.27 91.36 87.93 90.37
10000
Hz
105.48 85.62 87.47 95.29 90.31 85.79 91.58 86.55 90.28 86.05 87.27
Table 5.3-18 Los Angeles Memorial Coliseum EASE simulation scenario-2 total SPL at listeners seats
First arrival
First arrival timing mapping calculates the arrival time for any location from the nearest sound source.
EASE calculated the first arrival timings at 7 locations namely Student section-1, Student section-2, General
audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation are
exported as a table with the overall peak, average and minimum first arrival timings with the first arrival timings for
each location (Table 5.3-19) (Fig 5.3-18).
For 20 feet, recommended maximum arrival time is 17.9 microseconds (GB Audio, 2018). Presence of
loudspeakers on both the ends of the stadium posed a challenge of the sound reaching the farther stands. EASE
simulation mapping shows the sound takes longer to reach the stands higher up the stadium which explain the lower
SPL values. Student sections are in the closer proximity to the speaker systems which had the highest SPL values
recorded in the field study and the EASE simulation results. Uneven distribution of speakers is one of the prime
217
reasons for the higher range of SPL values between various audience stands. Though the first arrival mapping shows
the time taken for the direct sound to reach the location, it also shows the incident SPL received by the stands higher
are lower. The acoustic retrofit should reconfigure the speaker system to distribute sound equally towards all stands.
Figure 5.3-19 Los Angeles Memorial Coliseum EASE simulation first arrival mapping
First Arrival (ms)
Maximum 409.30
Minimum 0.00
Average 200.79
Student section-1 93.36
Student section-2 159.63
General Public-1 182.87
General Public-2 57.26
Titantron-1 73.98
Titantron-2 31.23
Southwest corner 126.70
Press Box-1 227.66
Table 5.3-19 Los Angeles Memorial Coliseum EASE simulation first arrival calculation at listeners seats
218
C7
C7 is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct
sound field (ADA (Acoustic Design Anhert), 2009). Values above -15 dB are considered good. Values closer to 0
dB are considered better (ADA (Acoustic Design Anhert), 2009). C7 mapping at the Coliseum for 1000 Hz was
simulated in EASE (Fig 5.3-19). EASE calculated the C7 values at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum C7 values with the C7 values for
each location (Table 5.3-20).
C7 values help to understand the ratio between direct sound and reverberant sound. It is calculated at an
interval of 7 microseconds between the direct and reflected sound. The average C7 values calculated by EASE are
within the acceptable value range however, the audience sections located farther from the speakers have
unacceptable values as highlighted in the results and the mapping. C7 values are in the unacceptable range as they
are located far away from the USC band speaker systems. The Titantron speakers are directed towards the eastern
end of the fieldfield which means the sound received in these stands are reflections from other stands. The acoustic
deficiencies can be fixed by reconfiguring the speaker system to distribute sound equally towards the stands.
219
Figure 5.3-20 Los Angeles Memorial Coliseum EASE simulation C7 mapping at 1000 Hz
FREQUENCY
MAXIMUM
(dB)
MINIMUM
(dB)
AVERAGE
(dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1
(dB)
GENERAL
PUBLIC-2
(dB)
TITANTRON-
1 (dB)
TITANTRON-
2 (dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 12.3 -24.79 -12.96 -3.09 -7.51 -17.9 -9.53 -12.54 -5.1 -14.63 -13.12
125 Hz 12.85 -23.99 -12.24 -2.23 -6.61 -17.35 -8.75 -11.94 -4.41 -13.87 -12.19
160 Hz 13.26 -22.65 -10.86 -0.55 -4.82 -16.22 -7.43 -11.03 -3.34 -12.52 -10.43
200 Hz 13.74 -21.39 -9.54 0.96 -3.26 -15.18 -6.46 -10.68 -2.77 -11.58 -8.89
250 Hz 14.43 -22.78 -8.77 2.61 -1.69 -15.83 -4.95 -9.99 -1.51 -10.44 -7.33
315 Hz 14.03 -21.84 -7.80 4.08 -0.22 -14.15 -4.43 -9.31 -1.19 -9.56 -5.91
400 Hz 11.95 -22.84 -7.45 4.79 0.41 -13.49 -4.29 -9.39 -1.18 -9.63 -5.31
500 Hz 13.09 -26.78 -7.16 5.29 1.33 -14.66 -2.61 -9.57 0.61 -8.45 -4.36
630 Hz 15.6 -31.6 -6.04 8.07 4.03 -16.98 -0.33 -7.66 2.14 -6.48 -1.74
800 Hz 16.95 -32.74 -6.09 10.81 7.06 -21.14 -0.21 -9.62 0.1 -6.4 1.32
1000 Hz 16.7 -31.2 -4.94 11.85 8.78 -19.32 -3.42 -10.97 -2.39 -6.52 3
1250 Hz 16.21 -27.69 -4.86 10.49 7 -16.5 -0.88 -10.6 0.9 -7.07 1.23
1600 Hz 17.68 -27.91 -5.27 10.63 7.16 -19.03 0.05 -12.02 0.33 -8.03 1.35
2000 Hz 17.69 -31.61 -5.42 11.42 7.99 -19.99 -0.96 -11.76 -1.08 -7.59 2.17
2500 Hz 18.81 -35.41 -6.24 12.14 7.79 -22.27 -0.69 -13.88 -0.98 -7.62 1.79
3150 Hz 19.41 -38.32 -7.14 13.06 7.88 -25.68 -1.24 -15.22 -2.38 -8.78 1.69
4000 Hz 19.56 -41 -7.44 13.1 8.57 -25.58 -1.97 -15.73 -4.06 -8.08 2.2
5000 Hz 19.82 -43.89 -8.57 12.71 8.73 -29.18 -2.05 -16.03 -4.71 -8.2 2
6300 Hz 19.54 -44.72 -9.42 12.43 8.23 -28.58 -0.67 -16.63 -3.34 -9.36 1.13
8000 Hz 19.71 -50.2 -11.60 11.62 7.74 -31.57 0.19 -16.25 -2.34 -10.23 0.07
10000
Hz
19.74 -50.94 -13.75 9.39 4.23 -30.34 2.23 -15.14 0.56 -13.03 -4.28
Table 5.3-20 Los Angeles Memorial Coliseum EASE simulation C7 calculation at listeners seats
220
C50
C50 measures the speech clarity which is the ratio between the early and late reflections in a space after 50
ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic
Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation (ADA
(Acoustic Design Anhert), 2009). C50 mapping at the Coliseum for 1000 Hz was simulated in EASE (Fig 4.3-27).
EASE calculated the C50 values at 7 locations namely Student section-1, Student section-2, General audience-1,
General audience-2, titantron, North-west corner, Away fans. The results from the simulation are exported as a table
with the overall peak, average and minimum C50 values with the C50 values for each location (Table 4.3-14) (Fig
4.3-28).
C50 values help to understand the ratio between early and late reflections. It is calculated at an interval of
50 microseconds between the direct and reflected sound. The average C50 values calculated by EASE are below the
acceptable value range. EASE mapping of C50 values shows that the stands in the General audience-1 stands have a
lower value due to their longer proximity from the speaker systems. C50 values are in the unacceptable range as
they are located far away from the USC band speaker systems. The Titantron speakers are directed towards the
eastern end of the fieldfield which means the sound received in these stands are reflections from other stands. The
acoustic deficiencies can be fixed by reconfiguring the speaker system to distribute sound equally towards the
stands.
221
Figure 5.3-21 Los Angeles Memorial Coliseum EASE simulation C50 mapping at 1000 Hz
FREQUENCY
MAXIMUM
(dB)
MINIMUM
(dB)
AVERAGE
(dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 12.56 -21.54 -9.31 -2.23 -5.82 -14.12 -6.39 -7.93 -3.02 -9.94 -9.21
125 Hz 13.13 -21.08 -8.65 -1.38 -4.99 -13.58 -5.65 -7.3 -2.3 -9.32 -8.49
160 Hz 13.58 -20 -7.44 0.27 -3.38 -12.54 -4.46 -6.38 -1.24 -8.32 -7.2
200 Hz 14.08 -18.7 -6.31 1.75 -1.96 -11.59 -3.63 -6.02 -0.8 -7.56 -6.04
250 Hz 14.82 -20.03 -5.57 3.4 -0.48 -12.02 -2.12 -5.28 0.64 -6.76 -4.81
315 Hz 14.51 -18.9 -4.64 4.89 0.94 -10.55 -1.73 -4.64 0.85 -6.11 -3.65
400 Hz 12.51 -20.04 -4.19 5.67 1.63 -9.97 -1.43 -4.6 1.06 -5.89 -3.03
500 Hz 13.69 -23.34 -3.72 6.26 2.57 -10.91 0.79 -4.54 3.57 -5.08 -2.16
630 Hz 16.34 -25.35 -2.69 8.98 5.09 -12.84 2.41 -2.9 4.17 -4.09 -0.1
800 Hz 17.69 -29.02 -2.26 11.67 7.97 -15.53 0.99 -5.62 0.89 -4.34 2.52
1000 Hz 17.52 -27.21 -1.43 12.72 9.67 -14.49 -1.62 -7.25 -0.39 -4.65 4.08
1250 Hz 17.05 -23.95 -1.59 11.44 8.01 -12.37 1.82 -6.13 2.78 -4.5 2.55
1600 Hz 18.51 -24.81 -1.9 11.59 8.19 -14.31 2.07 -7.45 1.92 -4.99 2.71
2000 Hz 18.52 -28.22 -1.77 12.37 8.98 -14.97 1.52 -7.6 0.2 -4.72 3.43
2500 Hz 19.67 -31.86 -2.12 13.11 8.82 -16.17 1.13 -9.12 0.19 -4.79 3.15
3150 Hz 20.29 -35.59 -2.36 14.04 8.93 -17.32 0.63 -10.4 -0.75 -5.29 3.09
4000 Hz 20.53 -37.41 -2.34 14.15 9.67 -17.22 0.04 -10.66 -2.67 -4.62 3.63
5000 Hz 20.89 -40.81 -2.51 13.88 9.94 -17.29 -0.32 -10.47 -3.07 -4.32 3.57
6300 Hz 20.77 -40.61 -2.7 13.77 9.64 -15.7 1.16 -9.88 -1.52 -4.12 3.07
8000 Hz 21.17 -46.13 -3.08 13.23 9.44 -14.4 2.41 -8.41 -0.14 -3.52 2.56
10000
Hz
21.61 -47.98 -3.61 11.5 6.68 -12.7 5.35 -6.2 3.26 -2.62 0.37
Table 5.3-21 Los Angeles Memorial Coliseum EASE simulation C50 calculation at listeners seats
222
C80
C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space. C80 mapping at the Coliseum for 1000 Hz was simulated in EASE (Fig
4.3-29). EASE calculated the C80 values at 7 locations namely Student section-1, Student section-2, General
audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation are
exported as a table with the overall peak, average and minimum C80 values with the C80 values for each location
(Table 4.3-15) (Fig 4.3-30).
C80 values help to evaluate the musical clarity of a space. It is calculated at an interval of 80 microseconds
between the direct and reflected sound. The average C80 values calculated by EASE are below the acceptable value
range. Acceptable range of C 80 values are from 0-8 dB. The stands within 30 feet radius of speakers (student
sections and away fans closer to field) have values higher than 8 dB and the stands father than 200-250 feet have
values lower than 0. These acoustic deficiencies can be fixed by reconfiguring the speaker system to distribute
sound equally towards the stands.
Figure 5.3-22 Los Angeles Memorial Coliseum EASE simulation C80 mapping at 1000 Hz
223
FREQUENCY
MAXIMUM
(dB)
MINIMUM
(dB)
AVERAGE
(dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1
(dB)
GENERAL
PUBLIC-2
(dB)
TITANTRON-
1 (dB)
TITANTRON-
2 (dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 12.86 -19.74 -6.41 -1.35 -4.33 -8.99 -4.79 -5.86 -2.05 -7.12 -6.69
125 Hz 13.47 -19.17 -5.74 -0.5 -3.53 -8.45 -4.08 -5.25 -1.33 -6.53 -6.02
160 Hz 13.97 -18 -4.58 1.14 -2.02 -7.58 -2.95 -4.33 -0.26 -5.6 -4.86
200 Hz 14.49 -16.84 -3.53 2.61 -0.68 -6.85 -2.13 -3.87 0.24 -4.87 -3.84
250 Hz 15.29 -17.41 -2.66 4.25 0.75 -6.71 -0.79 -3.22 1.6 -4.17 -2.72
315 Hz 15.07 -15.91 -1.74 5.77 2.14 -5.92 -0.38 -2.63 1.86 -3.61 -1.69
400 Hz 13.16 -15.25 -1.22 6.64 2.9 -5.37 -0.01 -2.45 2.14 -3.27 -1.03
500 Hz 14.41 -16.1 -0.64 7.31 3.88 -5.57 1.98 -2.29 4.51 -2.59 -0.18
630 Hz 17.8 -16.63 0.46 9.99 6.24 -6.89 3.27 -1.43 4.88 -2.09 1.54
800 Hz 19.08 -17.42 1.3 12.62 8.98 -8.54 1.72 -4.07 1.54 -2.59 3.82
1000 Hz 18.44 -16.46 1.94 13.68 10.66 -8.45 -0.8 -5.4 0.28 -3.07 5.25
1250 Hz 18.2 -17 1.62 12.49 9.14 -6.91 2.64 -4.11 3.46 -2.47 3.97
1600 Hz 19.49 -17.35 1.54 12.67 9.33 -7.52 2.89 -5.05 2.65 -2.75 4.16
2000 Hz 19.48 -18.26 1.81 13.42 10.07 -8.23 2.29 -5.54 0.89 -2.55 4.8
2500 Hz 20.67 -18.7 1.74 14.2 9.98 -8.32 2.02 -6.48 0.92 -2.66 4.62
3150 Hz 21.32 -19.05 1.83 15.14 10.1 -8.53 1.58 -7.43 0 -2.87 4.6
4000 Hz 21.66 -20.07 2.01 15.33 10.91 -8.18 1.07 -7.46 -1.7 -2.18 5.18
5000 Hz 22.18 -21.13 2.21 15.2 11.31 -7.5 0.87 -6.9 -1.91 -1.66 5.28
6300 Hz 22.26 -22.5 2.31 15.31 11.25 -5.53 2.55 -5.62 -0.13 -0.97 5.11
8000 Hz 22.95 -24.99 2.53 15.08 11.38 -3.64 4.04 -3.57 1.64 0.1 5.07
10000 Hz 23.87 -32.19 2.49 13.88 9.3 -1.39 7.72 -0.45 5.74 1.82 4
Table 5.3-22 Los Angeles Memorial Coliseum EASE simulation C80 calculation at listeners seats
Articulation loss of consonants (ALcons):
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable. EASE calculated the AL cons at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum AL cons percentages with the AL cons
percentages for each location (Table 4.3-16) (Fig 5.3-23).
Acoustic design standards had the maximum acceptable % AL cons to be 15% which has been reduced to
10% in recent years. The acceptable range for spaces like lecture halls where speech intelligibility is critical is 5%.
Similar to the other parameters, AL cons values are higher than acceptable range in the stands located farther from the
speaker systems. These acoustic deficiencies can be fixed by reconfiguring the speaker system to distribute sound
equally towards the stands.
224
Figure 5.3-23 Los Angeles Memorial Coliseum EASE simulation Articulation loss of consonants mapping
Articulation Loss of Consonants (ALC) (%)
Maximum 100
Minimum 1
Average
7.97
Student section-1
1.3
Student section-2
2.3
General Public-1
14.89
General Public-2
7.69
Titantron-1
11.94
Titantron-2
7.68
Southwest corner
14.74
Press Box-1
5.33
Table 5.3-23 Los Angeles Memorial Coliseum EASE simulation Articulation loss of consonants calculation at listeners seats
225
Speech transmission index (STI):
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009). EASE calculated the speech transmission index
at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron,
North-west corner, Away fans. The results from the simulation are exported as a table with the overall peak, average
and minimum speech transmission index with the speech transmission index for each location (Table 4.3-17) (Fig
4.3-32).
Speech transmission index(STI) values are higher than acceptable range in the stands located farther from
the speaker systems. These acoustic deficiencies can be fixed by reconfiguring the speaker system to distribute
sound equally towards the stands.
Figure 5.3-24 Los Angeles Memorial Coliseum EASE simulation speech transmission index (STI) mapping
226
Speech Transmission Index (STI)
Maximum 0.978
Minimum 0.00
Average
0.602
Student section-1
0.899
Student section-2
0.795
General Public-1
0.45
General Public-2
0.572
Titantron-1
0.491
Titantron-2
0.572
Southwest corner
0.452
Press Box-1
0.639
Table 5.3-24 Los Angeles Memorial Coliseum EASE simulation speech transmission index (STI) at listeners seats
EASE features
EASE was used to simulate the acoustic conditions of the Los Angeles Memorial Coliseum based on field
study observations. it was noticed that EASE can only simulate acoustic conditions with only constant ambient noise
throughout the space which was not the same with the Coliseum. The student section with the in-game chants were
always noisier than the other audience stands where most of the people just sit and watch the game. To overcome
this, two scenarios had to considered for simulation with one during the normal game play and other during exciting
in game moments such as USC touchdown, interception, sack etc. The only difference between the two scenarios
were in the SPL calculations while the other values were similar.
5.3.3 Takeaways for developing the retrofit for Coliseum
A partial roof system can be added over the northern and southern stands to reflect the sound towards the
field. The existing speaker system can be reconfigured to distribute equally towards all the audience stands to
improve overall acoustic quality.
5.4 Summary
The main purpose of conducting the acoustic field study at Harris Hall courtyard was for its similarity to a
stadium space with similar spatial configuration (open to sky with enclosed on sides) on a smaller scale. The field
study was not conducted with the notion of analyzing the space and the speaker placement configurations and
evaluate the acoustic conditions. The primary intent was to develop a Dynamo script to calculate all the acoustical
parameters. The speaker systems were placed in the study to maximize reflections so that the acoustic parameters
can be calculated using Dynamo. It was first tested by comparing real data from measurements in Harris Hall
227
courtyard to the simulation. The acoustic simulation of the courtyard provided slightly higher sound levels results
than the acoustic field study data, which is probably due to the presence of trees in the courtyard that could not be
modeled in the EASE model. There was sufficient data to conduct a detailed analysis but however the focus of the
study is concentrated on the Los Angeles Memorial Coliseum and the retrofit study and the Harris Hall courtyard
data can be used as a ground work for developing and valuating the Dynamo which is included in the possible future
study scope in chapter 7.
An acoustic field study was conducted during the 2017-18 college football season at the Los Angeles
Memorial Coliseum. Data collection from the field study at the Los Angeles Memorial Coliseum showed that the
Total SPL values recorded are not as high as it should be for a stadium with a capacity of 93500. Results showed
that the game against Texas Longhorns and the UCLA bruins recorded the highest sound pressure values due to the
higher stadium attendance. Both the games were played in the evening which had the larger crowd stay till the end
of the game. The Texas game went into extra time and had more exciting moments which had an influence on the
SPL values. Given the rivalry between USC Trojans and UCLA Bruins, the game had more excitement among the
audience and it was the last game of the season which resulted in higher SPL noises in the audience stands. The
game against Western Michigan despite being the season opener had a very low attendance due to the early kick off
time (02:15 PM) on a summer afternoon. Similarly, the Oregon State Beavers game also had similar attendance due
to the early kick off time (01:00 PM). Highest recorded value was 99.31 dB at the student section-1 and lowest
recorded value was 65.87 dB at the student section-2. Major reason for such lower SPL values is the absence of a
roof system which would help reflect the noise towards the field and to other audience stands which in turn would
make the audience cheer even more thereby increasing the overall SPL levels in the stadium. Also, the distribution
of the speaker systems is found to be inefficient as it does not reach the farther stands in the stadium. A retrofit with
a roof and a reconfigured sound system would improve the acoustic performance of the stadium.
Los Angeles Memorial Coliseum was simulated in EASE. The results from EASE simulation are described
below. Two scenarios were considered while simulating the acoustic conditions of the Coliseum. The input for
ambient noise varied in both the scenarios which are taken from the field study data collected at the Coliseum during
the 2017 football season. Scenario-1 calculated the Total SPL at lower ambient noise level. The mapping shows the
SPL levels are higher at the audience stands closer to the speaker systems. The placement of speaker systems played
a critical role in overall SPL values. EASE simulation mapping showed the audience stands closer to the speaker
228
systems had a higher SPL values which was similar to the field study observations. Possible reason for this was the
absence of a roof system that would have reflected the sound towards the audience stands and field.
The audience sections located farther from the speakers have unacceptable C7, C50, C80, AL cons
percentages, STI values as highlighted in the results and the mapping. The Titantron speakers are directed towards
the eastern end of the field; this means the sound received in these stands are reflections from other stands. The
acoustic deficiencies can be fixed by reconfiguring the speaker system to distribute sound equally towards the
stands.
EASE was used to simulate the acoustic conditions of the Los Angeles Memorial Coliseum based on field
study observations. it was noticed that EASE can only simulate acoustic conditions with only constant ambient noise
throughout the space which was not the same with the Coliseum. The student section with the in-game chants were
always noisier than the other audience stands where most of the people just sit and watch the game. To overcome
this, two scenarios had to considered for simulation with one during the normal game play and other during exciting
in game moments such as USC touchdown, interception, sack etc. The only difference between the two scenarios
were in the SPL calculations while the other values were similar.
Based on the analysis, two design retrofit options were proposed. The first option is based on the proposed
renovation of the Coliseum. The second option has a partial roof system over the north and south stands in the
proposed renovation and a reconfigured speaker system that are explained in chapter 6.
229
Chapter 6: Los Angeles Memorial Coliseum design modification
6.1 Overview
Following the analysis of the Los Angeles Memorial Coliseum, it was concluded that the noise generated
by audience is lesser compared to other sports arenas. Two design options are proposed, and an acoustic analysis of
the design options are made to look for any improvement in overall acoustic quality. The first option will be the new
proposed redesign of the Los Angeles Memorial Coliseum. The second option will have a partial roof system over
the northern and southern stands. Both the proposed options are simulated in EASE and analyzed to look for any
improvements.
Figure 6.1-1 Los Angeles Memorial Coliseum design modification analysis overview
6.2 Design modification-1
The existing Los Angeles Memorial Coliseum Sketchup model was edited to match the new proposed
design. Major changes were made in the south side with a large gallery space with private seating spaces (Fig 6.2-1).
A simplified model of the Coliseum design modification was made in AutoCAD. The .dwg file was then opened in
Sketchup to eliminate the unnecessary surfaces. All the surfaces which will not receive any reflections are
eliminated to facilitate the computing process during simulations. The model was simplified to the minimum and
exported as a Sketchup8 file, which is an older version of the Sketchup software as EASE supports only up to
Sketchup 8 files for import.
230
Figure 6.2-1 Los Angeles Memorial Coliseum design modifcation-1 (proposed renovation)
6.2.1 EASE simulation analysis
EASE supports importing geometry from DXF and SKP (Sketchup) formats. The Revit model of the
Coliseum had more surfaces which would have taken longer for computation. Hence a simplified model of the
Coliseum was made in AutoCAD 3D and was exported as a DXF file (Fig 6.2-2). The curvilinear surfaces were
simplified into planar polygons to reduce the complexity of the geometry and reduce simulation times. The DXF file
was then opened in Sketchup to eliminate the unnecessary surfaces. All the surfaces that did not receive any
reflections were eliminated to expedite the computing process during simulations. The model was simplified to the
minimum and exported as a Sketchup8 file which is the format supported by EASE.
231
Figure 6.2-2 Los Angeles Memorial Coliseum design modification-1 AutoCAD 3d model
The materials were applied on the Sketchup model as that made it easier to apply materials on EASE. The
Sketchup model was purged to remove any unnecessary lines and objects to reduce the file size. The model was
exploded to sure that it becomes a single piece than several groups or components in Sketchup (Fig 6.2-3). After
exploding the model, the “intersect faces” option was chosen to make sure that all the faces are connected to each
other. Failing to perform this step will result in finding holes in the model when imported into EASE.
232
Figure 6.2-3 Los Angeles Memorial Coliseum design modification-1 Sketchup model
A new project file is setup in EASE and the “Import CAD/DXF” option was used to import the Sketchup
model. EASE detects the materials applied on Sketchup model and provides an option to choose to apply any
material from EASE material database while importing (Table 6.2-1). Similarly EASE also detects layers in a CAD
drawing and has an option to apply materials from EASE material database to each layer.
S.NO MATERIAL EASE MATERIAL NAME DESCRIPTION
1. Walls Generic, Brick, Unglazed,
Painted
Brick, unglazed, painted1 Octave Data: 125Hz-
4KHz Data from Sound System Engineering, 2
nd
Edition, pgs 158-159
2. Brick floor Generic, Brick, Unglazed Unglazed Bricks1 Octave Data: 125Hz-8KHz
Data from: Architectural Acoustics M David
Egan pg 52
3. Grass Generic, Grass, 2 inch thk Grass, Marion bluegrass 2" high 1 Octave Data:
125Hz-4KHz. Data from Architectural Acoustics
M David Egan pg 52
4. Glazing over
press box
Generic, Glass, Window,
Plate, 0,25 inch thk, Heavy
Large Panes
Plate glass, Large Heavy Panes 1 Octave Data:
125Hz-4KHz Data From sound system
engineering, 2nd Edition, pgs 158-159
5. Concrete Generic, Concrete, Rough
Finish
Concrete wall or floor, Rough Finish 1 Octave
Data: 125Hz-4KHz Data Unattributed
6. Audience
stands
Generic, People, in Fully
Covered Seats, per Person
People in fully covered seats per person
1 Octave Data: 125Hz-4KHz
Data From Audio System Designer Technical
Handbook
Table 6.2-1 Los Angeles Memorial Coliseum redesign-1 EASE material list
233
After importing the DXF/Sketchup model, the model was checked for any holes or errors using the “Check
holes” option in the “edit room” window. Any errors or holes are fixed in the model by using the “Close holes”
option in the “Check holes” window. Once the model was cleared of errors, the speaker systems, audience seats
were imported as an ASCII file from the existing Coliseum EASE file using the “Import/Export” option for
consistency in the measurement points. The audience area was defined by drawing a quadrilateral over the stands in
the model to suit the modified audience stands in the redesign (Fig 6.2-4).
Figure 6.2-4 Los Angeles Memorial Coliseum design modification-1 EASE model
After defining the audience area, the model was inspected for any missing elements. Check data option was
run to find any errors in the model and it was rectified. The “Compute data” option was run for EASE to analyze the
model. The model was checked again for holes or errors. After fixing errors, the “Edit Room” window was closed,
and the “Aura” module was loaded in EASE.
Mapping module contains 2D mapping, 3D mapping, rendered view of the model, C7 mapping, C50
mapping, first arrival time mapping, loudspeaker overlaps mapping. Each of the functions run as a separate
simulation while loaded and the results are showed as mapping with a color scale. All the mapping renders were
exported as an image. The results are also shown as tables and graphs based on the frequency range that can be
exported as an Excel spreadsheet. The results from the EASE simulation of the Los Angeles Memorial Coliseum
redesign-1 are described in section 6.2.2.
234
6.2.2 EASE simulation results
Los Angeles Memorial Coliseum design modification-1 was simulated in EASE. The results from EASE
simulation are described below. Two scenarios were considered while simulating the acoustic conditions of the
Coliseum (Fig (6.2-5). The input for ambient noise varied in both the scenarios which are taken from the field study
data collected at the Coliseum during the 2017 football season.
Figure 6.2-5 Los Angeles Memorial Coliseum design modification-1 EASE simulation results overview
Total SPL
Scenario-1
Total sound pressure level (SPL) mapping at 1000 Hz for Coliseum design modification-1 scenario-1 was
simulated in EASE (Fig 6.2-6). The overall sound pressure levels at each location of the Coliseum can be interpreted
from the mapping. Color scaled mapping can be useful to interpret uneven distribution of sound and speaker system
throughout the space. EASE calculated the sound pressure levels at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum sound pressure values with the sound
pressure levels for each location (Table 6.2-2) (Fig 6.2-7).
235
Figure 6.2-6 Los Angeles Memorial Coliseum design modification-1 scenario-1 EASE simulation total SPL mapping at 1000 Hz
236
FREQUENCY
MAXIMUM (dBA)
MINIMUM (dBA)
AVERAGE (dBA)
STUDENT
SECTION-1 (dBA)
STUDENT
SECTION-2 (dBA)
GENERAL
PUBLIC-1 (dBA)
GENERAL
PUBLIC-2 (dBA)
TITANTRON-1
(dBA)
TITANTRON-2
(dBA)
SOUTHWEST
CORNER (dBA)
PRESS BOX-1
(dBA)
100 Hz 66.89 60.65 60.87 61.18 60.87 60.75 60.99 60.92 61.41 60.77 60.87
125 Hz 71.23 64.76 65 65.36 65.01 64.88 65.15 65.06 65.6 64.9 65.01
160 Hz 73.54 66.57 66.89 67.38 66.92 66.73 67.07 66.94 67.59 66.76 66.92
200 Hz 76.56 68.05 68.44 69.12 68.51 68.24 68.64 68.46 69.14 68.28 68.51
250 Hz 79.75 70.74 71.2 72.17 71.32 70.94 71.54 71.25 72.17 71.02 71.32
315 Hz 79.29 70.78 71.3 72.45 71.46 71.03 71.63 71.35 72.22 71.11 71.46
400 Hz 80.68 73.1 73.6 74.8 73.77 73.35 73.92 73.63 74.47 73.41 73.77
500 Hz 84.56 76.81 77.35 78.51 77.54 77.05 77.97 77.33 78.82 77.15 77.54
630 Hz 85.97 75.59 76.46 78.49 76.88 75.97 77.48 76.6 78.33 76.13 76.88
800 Hz 82.92 72.5 73.74 77.04 74.75 73.06 74.53 73.79 74.82 73.26 74.75
1000 Hz 82.18 72.62 73.91 77.46 75.37 73.21 74.32 73.9 74.79 73.55 75.37
1250 Hz 83.34 73.33 74.34 77.18 75.23 73.75 75.19 74.27 75.77 73.92 75.23
1600 Hz 84.98 74.22 75.28 78.31 76.23 74.65 76.17 75.16 76.45 74.76 76.23
2000 Hz 85.72 74.6 75.87 79.66 77.14 75.15 76.66 75.91 76.88 75.18 77.14
2500 Hz 84.8 72.59 73.93 78.37 75.16 73.15 74.52 73.94 74.99 73.28 75.16
3150 Hz 84.64 71.18 72.72 78.31 74.16 71.81 73.2 72.89 73.78 71.86 74.16
4000 Hz 82.09 68.07 69.77 75.88 71.76 68.74 70.17 69.97 70.55 68.77 71.76
5000 Hz 81.27 66.65 68.44 74.6 70.87 67.3 68.78 68.51 69.15 67.34 70.87
6300 Hz 80.22 65.13 66.78 73.27 69.22 65.54 67.48 66.63 67.46 65.66 69.22
8000 Hz 78.46 62.58 64.13 70.67 66.72 62.82 65.32 63.61 64.77 63.01 66.72
10000 Hz 77.7 60.95 62.04 67.22 63.41 61.02 64.28 61.34 63.39 61.13 63.41
Table 6.2-2 Los Angeles Memorial Coliseum design modification-1EASE simulation scenario-1 total SPL calculation at listeners
seats
Figure 6.2-7 Los Angeles Memorial Coliseum design modification-1 EASE simulation scenario-1 total SPL calculation at
listeners seats
237
Scenario-2
Total sound pressure level (SPL) mapping at 1000 Hz for Coliseum redesign-1 scenario-2 was simulated in
EASE (Fig 6.2-8). The overall sound pressure levels at each location of the Coliseum can be interpreted from the
mapping. Color scaled mapping can be useful to interpret uneven distribution of sound and speaker system
throughout the space. EASE calculated the sound pressure levels at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum sound pressure values with the sound
pressure levels for each location (Table 6.2-3) (Fig 6.2-9).
Figure 6.2-8 Los Angeles Memorial Coliseum design modification-1 scenario-2 EASE simulation total SPL mapping at 1000 Hz
238
FREQUENCY
MAXIMUM (dBA)
MINIMUM (dBA)
AVERAGE (dBA)
STUDENT
SECTION-1 (dBA)
STUDENT
SECTION-2 (dBA)
GENERAL
PUBLIC-1 (dBA)
GENERAL
PUBLIC-2 (dBA)
TITANTRON-1
(dBA)
TITANTRON-2
(dBA)
SOUTHWEST
CORNER (dBA)
PRESS BOX-1
(dBA)
100 Hz 81.89 75.65 75.87 76.18 75.87 75.75 75.99 75.92 76.41 75.77 75.79
125 Hz 86.23 79.76 80 80.36 80.01 79.88 80.15 80.06 80.6 79.9 79.92
160 Hz 88.54 81.57 81.89 82.38 81.92 81.73 82.07 81.94 82.59 81.76 81.79
200 Hz 91.56 83.05 83.44 84.12 83.51 83.24 83.64 83.46 84.14 83.28 83.34
250 Hz 94.75 85.74 86.2 87.17 86.32 85.94 86.54 86.25 87.17 86.02 86.08
315 Hz 94.29 85.78 86.3 87.45 86.46 86.03 86.63 86.35 87.22 86.11 86.19
400 Hz 95.68 88.1 88.6 89.8 88.77 88.35 88.92 88.63 89.47 88.41 88.51
500 Hz 99.56 91.81 92.35 93.51 92.54 92.05 92.97 92.33 93.82 92.15 92.25
630 Hz 100.97 90.59 91.46 93.49 91.88 90.97 92.48 91.6 93.33 91.13 91.28
800 Hz 97.92 87.5 88.74 92.04 89.75 88.06 89.53 88.79 89.82 88.26 88.76
1000 Hz 97.18 87.62 88.91 92.46 90.37 88.21 89.32 88.9 89.79 88.55 89.34
1250 Hz 98.34 88.33 89.34 92.18 90.23 88.75 90.19 89.27 90.77 88.92 89.52
1600 Hz 99.98 89.22 90.28 93.31 91.23 89.65 91.17 90.16 91.45 89.76 90.42
2000 Hz 100.72 89.6 90.87 94.66 92.14 90.15 91.66 90.91 91.88 90.18 91.03
2500 Hz 99.8 87.59 88.93 93.37 90.16 88.15 89.52 88.94 89.99 88.28 89.06
3150 Hz 99.64 86.18 87.72 93.31 89.16 86.81 88.2 87.89 88.78 86.86 87.75
4000 Hz 97.09 83.07 84.77 90.88 86.76 83.74 85.17 84.97 85.55 83.77 84.96
5000 Hz 96.27 81.65 83.44 89.6 85.87 82.3 83.78 83.51 84.15 82.34 83.69
6300 Hz 95.22 80.13 81.78 88.27 84.22 80.54 82.48 81.63 82.46 80.66 82.04
8000 Hz 93.46 77.58 79.13 85.67 81.72 77.82 80.32 78.61 79.77 78.01 79.34
10000 Hz 92.7 75.95 77.04 82.22 78.41 76.02 79.28 76.34 78.39 76.13 76.79
Table 6.2-3 Los Angeles Memorial Coliseum design modification-1 scenario-2 EASE simulation total SPL at listeners seats
Figure 6.2-9 Los Angeles Memorial Coliseum design modification-1 EASE simulation scenario-2 total SPL calculation at
listeners seats
239
First arrival
First arrival timing mapping calculates the arrival time for any location from the nearest sound source.
EASE calculated the first arrival timings at 7 locations namely Student section-1, Student section-2, General
audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation are
exported as a table with the overall peak, average and minimum first arrival timings with the first arrival timings for
each location (Table 6.2-4) (Fig 6.2-10).
Figure 6.2-10 Los Angeles Memorial Coliseum design modification-1 EASE simulation first arrival mapping
First Arrival (ms)
Maximum
600.84
Minimum
0
Average
205.05
Student section-1
91.59
Student section-2
158.56
General Public-1
182.87
General Public-2
57.25
Titantron-1
73.98
Titantron-2
31.23
Southwest corner
126.7
Press Box-1
215.03
Table 6.2-4 Los Angeles Memorial Coliseum design modification-1 first arrival calculation at listeners seats
240
C7
C7 is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct
sound field (ADA (Acoustic Design Anhert), 2009). Values above -15 dB are considered good. Values closer to 0
dB are considered better (ADA (Acoustic Design Anhert), 2009). C7 mapping at the Coliseum redesign-1 for 1000
Hz was simulated in EASE (Fig 6.2-11). EASE calculated the C7 values at 7 locations namely Student section-1,
Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results
from the simulation are exported as a table with the overall peak, average and minimum C7 values with the C7
values for each location (Table 6.2-5) (Fig 6.2-12).
Figure 6.2-11 Los Angeles Memorial Coliseum design modification-1 EASE simulation C7 mapping at 1000 Hz
241
FREQUENCY
MAXIMUM
(dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 4.79 -35.91 -18.08 -9.51 -14 -21.9 -13.46 -16.43 -8.91 -18.68 -16.68
125 Hz 5.07 -35.74 -17.59 -8.88 -13.34 -21.57 -12.87 -16.03 -8.4 -18.15 -15.99
160 Hz 5.68 -35.15 -16.49 -7.49 -11.86 -20.69 -11.76 -15.33 -7.53 -17.06 -14.51
200 Hz 7.47 -33.92 -15.42 -6.13 -10.55 -19.83 -10.97 -15.16 -7.17 -16.35 -13.21
250 Hz 8.05 -35.79 -14.9 -4.53 -9.22 -20.65 -9.53 -14.56 -5.94 -15.42 -11.98
315 Hz 7.53 -37.53 -14.35 -3.63 -8.28 -19.26 -9.31 -14.13 -5.92 -14.86 -10.92
400 Hz 6.48 -38.75 -14.45 -3.47 -8.23 -19.02 -9.55 -14.6 -6.26 -15.36 -10.78
500 Hz 6.76 -39.9 -14.46 -3.39 -7.75 -20.54 -7.86 -15.13 -4.35 -14.61 -10.38
630 Hz 9.81 -41.45 -13.17 -0.37 -4.89 -22.3 -5.17 -12.47 -2.57 -12.49 -8.2
800 Hz 9.89 -44.32 -13.07 2.47 -2 -25.7 -4.92 -13.86 -4.41 -12.03 -5.24
1000 Hz 8.92 -41.36 -12.29 2.93 -0.82 -23.82 -7.76 -15.2 -6.46 -11.87 -3.56
1250 Hz 9.42 -41.29 -12.61 1.39 -2.86 -21.81 -5.74 -15.55 -3.84 -13.23 -5.4
1600 Hz 10.25 -41.63 -12.88 1.81 -2.52 -24.2 -4.95 -16.88 -4.46 -14.21 -5.35
2000 Hz 10.61 -44.29 -12.72 3.28 -1.25 -24.49 -5.44 -15.95 -5.37 -13.64 -4.5
2500 Hz 11.8 -46.42 -13.17 4.33 -1.15 -26.41 -5.28 -17.75 -4.99 -13.07 -4.29
3150 Hz 13.14 -50.95 -13.51 6.05 -0.31 -29.21 -5.36 -18.44 -5.71 -13.84 -3.98
4000 Hz 13.75 -51.67 -13.32 6.9 1.08 -28.69 -5.58 -18.55 -7.04 -12.76 -2.94
5000 Hz 14.41 -56.74 -13.98 7.12 2.03 -31.99 -5.36 -18.64 -7.36 -12.44 -2.47
6300 Hz 17.41 -57.19 -14.39 7.39 1.9 -31.63 -3.82 -19.24 -6.03 -13.19 -2.7
8000 Hz 23.28 -200 -16.13 7.35 2.01 -34.58 -2.53 -18.85 -4.94 -13.55 -3.05
10000 Hz 32.5 -200 -18.08 5.09 -1.2 -33.41 -0.44 -18 -2.23 -16.14 -6.74
Table 6.2-5 Los Angeles Memorial Coliseum design modification-1 EASE simulation C7 calculation at listeners seats
Figure 6.2-12 Los Angeles Memorial Coliseum design modification-1 EASE simulation C7 calculation at listeners seats
242
C50
C50 measures the speech clarity which is the ratio between the early and late reflections in a space after 50
ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic
Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation (ADA
(Acoustic Design Anhert), 2009). C50 mapping at the Coliseum redesign-1 for 1000 Hz was simulated in EASE
(Fig 6.2-13). EASE calculated the C50 values at 7 locations namely Student section-1, Student section-2, General
audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation are
exported as a table with the overall peak, average and minimum C50 values with the C50 values for each location
(Table 6.2-6) (Fig 6.2-14).
Figure 6.2-13 Los Angeles Memorial Coliseum design modification-1 EASE simulation C50 mapping at 1000 Hz
243
FREQUENCY
MAXIMUM
(dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 4.92 -35.86 -13.99 -8.55 -11.8 -18.22 -10.61 -12.1 -7.19 -14.23 -13.28
125 Hz 5.22 -35.66 -13.55 -7.95 -11.23 -17.89 -10.08 -11.69 -6.7 -13.78 -12.74
160 Hz 5.84 -35.09 -12.61 -6.65 -10 -17.05 -9.11 -11 -5.88 -12.92 -11.62
200 Hz 7.64 -33.92 -11.72 -5.38 -8.89 -16.27 -8.45 -10.8 -5.64 -12.26 -10.62
250 Hz 8.25 -35.79 -11.21 -3.88 -7.75 -16.77 -7.11 -10.18 -4.37 -11.55 -9.64
315 Hz 7.75 -37.33 -10.66 -3 -6.92 -15.6 -6.96 -9.8 -4.41 -11.07 -8.8
400 Hz 6.74 -37.77 -10.58 -2.8 -6.76 -15.37 -7 -10.07 -4.59 -11.02 -8.54
500 Hz 7.04 -37.29 -10.38 -2.67 -6.28 -16.43 -5.21 -10.25 -2.5 -10.48 -8.13
630 Hz 10.08 -38.2 -9.34 0.15 -3.93 -17.51 -3.22 -8.15 -1.29 -9.42 -6.56
800 Hz 10.19 -43.72 -8.78 2.89 -1.33 -18.92 -3.78 -9.74 -3.59 -9.15 -4.19
1000 Hz 9.24 -40.92 -8.3 3.35 -0.22 -17.93 -5.81 -10.98 -4.58 -9.02 -2.7
1250 Hz 9.75 -39.97 -8.7 1.89 -2.04 -16.84 -3.61 -10.67 -2.43 -9.46 -4.21
1600 Hz 10.59 -41.63 -8.76 2.31 -1.7 -18.16 -3.29 -11.57 -3.11 -9.73 -4.13
2000 Hz 10.96 -43.34 -8.34 3.75 -0.52 -18.08 -3.35 -11.1 -4.04 -9.36 -3.37
2500 Hz 12.18 -46.42 -8.26 4.81 -0.36 -18.62 -3.57 -12 -3.73 -8.94 -3.1
3150 Hz 13.56 -50.13 -7.92 6.54 0.49 -18.88 -3.53 -12.44 -3.99 -8.92 -2.73
4000 Hz 14.24 -50.67 -7.4 7.46 1.88 -18.41 -3.52 -12.27 -5.28 -8.06 -1.69
5000 Hz 15 -55.65 -7.01 7.79 2.92 -18.08 -3.41 -11.83 -5.28 -7.36 -1.07
6300 Hz 18.72 -56.29 -6.64 8.23 3.03 -16.88 -1.87 -11.11 -3.84 -6.7 -0.91
8000 Hz 24.99 -63.07 -6.27 8.46 3.49 -15.63 -0.3 -9.67 -2.43 -5.61 -0.64
10000 Hz 34.88 -200 -6.03 6.78 1.46 -14 2.33 -7.7 0.49 -4.31 -1.88
Table 6.2-6 Los Angeles Memorial Coliseum design modification-1 EASE simulation C50 calculation at listeners seats
Figure 6.2-14 Los Angeles Memorial Coliseum design modification-1 EASE simulation C50 calculation at listeners seats
244
C80
C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space. C80 mapping at the Coliseum redesign-1 for 1000 Hz was simulated in
EASE (Fig 6.2-15). EASE calculated the C80 values at 7 locations namely Student section-1, Student section-2,
General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation
are exported as a table with the overall peak, average and minimum C80 values with the C80 values for each
location (Table 6.2-7) (Fig 6.2-16).
Figure 6.2-15 Los Angeles Memorial Coliseum design modification-1 EASE simulation C80 mapping at 1000 Hz
245
FREQUENCY
MAXIMUM
(dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 5.09 -30.21 -11.12 -7.57 -10.04 -13.32 -9.19 -10.24 -6.43 -11.55 -10.99
125 Hz 5.4 -29.68 -10.68 -7 -9.51 -12.94 -8.69 -9.83 -5.94 -11.12 -10.5
160 Hz 6.05 -28.42 -9.78 -5.77 -8.41 -12.17 -7.76 -9.11 -5.12 -10.31 -9.51
200 Hz 7.86 -27.14 -8.96 -4.57 -7.41 -11.49 -7.1 -8.76 -4.81 -9.66 -8.62
250 Hz 8.49 -26.43 -8.32 -3.16 -6.39 -11.28 -5.92 -8.16 -3.61 -9.01 -7.76
315 Hz 8.02 -25.76 -7.77 -2.3 -5.63 -10.61 -5.7 -7.76 -3.58 -8.55 -7.02
400 Hz 7.05 -25.81 -7.56 -2.05 -5.39 -10.25 -5.62 -7.77 -3.66 -8.33 -6.7
500 Hz 7.39 -25.82 -7.22 -1.87 -4.9 -10.29 -4.09 -7.72 -1.75 -7.84 -6.27
630 Hz 10.42 -24.88 -6.18 0.75 -2.92 -10.48 -2.38 -6.36 -0.65 -7.14 -5.05
800 Hz 10.55 -22.89 -5.3 3.38 -0.59 -10.7 -2.88 -7.51 -2.76 -6.95 -3.09
1000 Hz 9.63 -21.36 -4.95 3.85 0.47 -10.32 -4.57 -8.19 -3.6 -6.83 -1.77
1250 Hz 10.15 -23.19 -5.4 2.47 -1.15 -9.81 -2.61 -7.76 -1.61 -6.91 -3.01
1600 Hz 11 -23.66 -5.26 2.9 -0.81 -9.93 -2.3 -8.17 -2.19 -6.98 -2.89
2000 Hz 11.39 -22.93 -4.73 4.31 0.29 -9.8 -2.33 -7.99 -3.01 -6.65 -2.2
2500 Hz 12.64 -23.32 -4.41 5.39 0.51 -9.57 -2.43 -8.29 -2.68 -6.27 -1.88
3150 Hz 14.07 -23.43 -3.8 7.14 1.38 -9.21 -2.3 -8.45 -2.86 -6.03 -1.44
4000 Hz 14.83 -23.64 -3.11 8.13 2.79 -8.59 -2.16 -8.11 -3.8 -5.19 -0.39
5000 Hz 15.71 -24.8 -2.39 8.59 3.92 -7.79 -1.86 -7.41 -3.6 -4.36 0.36
6300 Hz 19.62 -26.61 -1.71 9.23 4.29 -6.42 -0.23 -6.19 -2.01 -3.35 0.86
8000 Hz 26.18 -29.95 -0.75 9.79 5.12 -4.83 1.52 -4.36 -0.29 -1.92 1.61
10000 Hz 36.54 -38.64 0.01 8.72 4.01 -2.89 4.59 -1.8 3.02 -0.05 1.51
Table 6.2-7 Los Angeles Memorial Coliseum design modification-1 EASE simulation C80 calculation at listeners seats
Figure 6.2-16 Los Angeles Memorial Coliseum design modification-1 EASE simulation C80 calculation at listeners seats
246
Articulation loss of consonants
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable. EASE calculated the AL cons at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum AL cons percentages with the AL cons
percentages for each location (Table 6.2-8) (Fig 6.2-17).
Figure 6.2-17 Los Angeles Memorial Coliseum design modification-1 EASE simulation Articulation loss of consonants mapping
Articulation Loss of Consonants (ALC) (%)
Maximum
100
Minimum
1.68
Average
23.72
Student section-1
5.62
Student section-2
11.39
General Public-1
36.21
General Public-2
17.26
Titantron-1
29.76
Titantron-2
16.73
Southwest corner
30.28
Press Box-1
16.75
Table 6.2-8 Los Angeles Memorial Coliseum design modification-1 EASE simulation Articulation loss of consonants calculation
at listeners seats
247
Speech transmission index
Speech Transmission Index is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009). EASE calculated the speech transmission index
at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron,
North-west corner, Away fans. The results from the simulation are exported as a table with the overall peak, average
and minimum speech transmission index with the speech transmission index for each location (Table 6.2-9) (Fig
6.2-18).
Figure 6.2-18 Los Angeles Memorial Coliseum design modification EASE simulation speech transmission index (STI) mapping
Speech Transmission Index (STI)
Maximum
0.852
Minimum
0
Average
0.319
Student section-1
0.63
Student section-2
0.499
General Public-1
0.286
General Public-2
0.423
Titantron-1
0.322
Titantron-2
0.428
Southwest corner
0.319
Press Box-1
0.428
Table 6.2-9 Los Angeles Memorial Coliseum design modification-1 EASE simulation speech transmission index (STI) calculation
at listeners’ seats
248
6.3 Design modification-2
A partial roof system was added to the north and south stands of the design modification -1. The partial roof
was designed to trap the sound inside the stadium reflect the audience noise towards the pitch (Fig 6.3-1) (Fig 6.3-
2). ETFE (Ethylene tetrafluoroethylene) was considered for roof material for its light weight and reflective
properties. ETFE has been used for stadium facades and roof systems for the same reasons. The structural system to
support the roof system has not been discussed as the study only focuses on the acoustical analysis and the
improvement the roof system provides over existing conditions.
Figure 6.3-1 Los Angeles Memorial Coliseum design modification-2 section through the Sketchup model
Figure 6.3-2 Los Angeles Memorial Coliseum design modification-2 view inside the Coliseum Sketchup model
249
6.3.1 EASE simulation analysis
EASE supports importing geometry from DXF and SKP (Sketchup) formats. The Revit model of the
Coliseum had more surfaces which would have taken longer for computation. Hence a simplified model of the
Coliseum was made in AutoCAD and was exported as a DXF file (Fig 6.3-3). The curvilinear surfaces were
simplified into planar polygons to reduce the complexity of the geometry and reduce simulation times. The DXF file
was then opened in Sketchup to eliminate the unnecessary surfaces. All the surfaces that did not receive any
reflections were eliminated to expedite the computing process during simulations. The model was simplified to the
minimum and exported as a Sketchup8 file which is the format supported by EASE (Fig 6.3-4).
Figure 6.3-3 Los Angeles Memorial Coliseum design modification-2 AutoCAD 3d model
The materials were applied on the Sketchup model as that made it easier to apply materials on EASE. The
Sketchup model was purged to remove any unnecessary lines, objects, and reduce the file size. The model was
exploded to sure that it becomes a single piece than several groups or components in Sketchup. After exploding the
model, the “intersect faces” option was chosen to make sure that all the faces are connected to each other. Failing to
perform this step will result in finding holes in the model when imported into EASE.
250
Figure 6.3-4 Los Angeles Memorial Coliseum design modification-2 Sketchup model
A new project file is setup in EASE and the “Import CAD/DXF” option was used to import the Sketchup
model. EASE detects the materials applied on Sketchup model and provides an option to choose to apply any
material from EASE material database while importing. Similarly EASE also detects layers in a CAD drawing and
has an option to apply materials from EASE material database to each layer (Table 6.3-1).
S.NO MATERIAL EASE MATERIAL NAME DESCRIPTION
1. Walls Generic, Brick, Unglazed,
Painted
Brick, unglazed, painted1 Octave Data: 125Hz-
4KHz Data from Sound System Engineering, 2
nd
Edition, pgs 158-159
2. Brick floor Generic, Brick, Unglazed Unglazed Bricks1 Octave Data: 125Hz-8KHz
Data from: Architectural Acoustics M David
Egan pg 52
3. Grass Generic, Grass, 2 inch thk Grass, Marion bluegrass 2" high 1 Octave Data:
125Hz-4KHz. Data from Architectural Acoustics
M David Egan pg 52
4. Glazing over
press box
Generic, Glass, Window,
Plate, 0,25 inch thk, Heavy
Large Panes
Plate glass, Large Heavy Panes 1 Octave Data:
125Hz-4KHz Data From sound system
engineering, 2nd Edition, pgs 158-159
5. Concrete Generic, Concrete, Rough
Finish
Concrete wall or floor, Rough Finish 1 Octave
Data: 125Hz-4KHz Data Unattributed
6. Audience
stands
Generic, People, in Fully
Covered Seats, per Person
People in fully covered seats per person
1 Octave Data: 125Hz-4KHz
Data From Audio System Designer Technical
Handbook
Table 6.3-1 Los Angeles Memorial Coliseum design modification-2 EASE material list
251
After importing the DXF/Sketchup model, the model was checked for any holes or errors using the “Check
holes” option in the “edit room” window. Any errors or holes are fixed in the model by using the “Close holes”
option in the “Check holes” window. Once the model was cleared of errors, the speaker systems, audience seats,
audience areas were imported as an ASCII file from the existing Coliseum redesign-1 EASE file using the
“Import/Export” option for consistency in the measurement points (Fig 6.3-5).
Figure 6.3-5 Los Angeles Memorial Coliseum design modification-2 EASE model
After defining the audience area, the model was inspected for any missing elements. Check data option was
run to find any errors in the model and it was rectified. The “Compute data” option was run for EASE to analyze the
model. The model was checked again for holes or errors. After fixing errors, the “Edit Room” window was closed,
and the “Aura” module was loaded in EASE.
Mapping module contains 2D mapping, 3D mapping, rendered view of the model, C7 mapping, C50
mapping, first arrival time mapping, loudspeaker overlaps mapping. Each of the functions run as a separate
simulation while loaded and the results are showed as mapping with a color scale. All the mapping renders were
exported as an image. The results are also shown as tables and graphs based on the frequency range that can be
exported as an Excel spreadsheet. The results from the EASE simulation of the Los Angeles Memorial Coliseum are
described in section.
252
6.3.2 EASE simulation results
Los Angeles Memorial Coliseum design modification-2 was simulated in EASE. The results from EASE
simulation are described below. Two setups were considered with the first setup consisting of the existing speaker
setup in the stadium. Setup-2 had an alternate speaker layout with the speakers focusing on the audience stands form
the partial roof system. Two scenarios were considered while simulating the acoustic conditions of the Coliseum.
The input for ambient noise varied in both the scenarios which are taken from the field study data collected at the
Coliseum during the 2017 football season.
Figure 6.3-6 Los Angeles Memorial Coliseum design modification-2 results overview
Total SPL
Two different setups were simulated in EASE for the Los Angeles Memorial Coliseum redesign-2 and have
been described in the following sections.
Setup-1
Los Angeles Memorial Coliseum redesign-2 setup-1 has a partial roof system over the north and south
audience stands with the existing speaker systems (Fig 6.3-7).
253
Figure 6.3-7 Los Angeles Memorial Coliseum design modification-2 setup-1 layout
Scenario-1
Total sound pressure level (SPL) at the Coliseum redesign-2 ssetup-1mapping at 1000 Hz for scenario-1 was
simulated in EASE (Fig 6.3-8). The overall sound pressure levels at each location of the Coliseum can be interpreted
from the mapping. Color scaled mapping can be useful to interpret uneven distribution of sound and speaker system
throughout the space. EASE calculated the sound pressure levels at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum sound pressure values with the sound
pressure levels for each location (Table 6.3-2) (Fig 6.3-9).
Figure 6.3-8 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-1 total SPL mapping at
1000 Hz
254
FREQUENCY
MAXIMUM
(dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 66.12 55.68 56.31 57.18 56.35 56.01 56.68 56.48 57.72 56.06 56.12
125 Hz 70.51 59.87 60.55 61.52 60.61 60.22 60.97 60.74 62.08 60.29 60.35
160 Hz 72.94 62.14 62.91 64.08 63.04 62.55 63.4 63.09 64.53 62.64 62.72
200 Hz 76.17 63.99 64.87 66.33 65.08 64.46 65.36 64.97 66.36 64.55 64.7
250 Hz 79.42 67.06 68.01 69.87 68.31 67.52 68.74 68.16 69.86 67.69 67.83
315 Hz 78.94 67.29 68.33 70.41 68.7 67.84 69.01 68.48 70.04 68.01 68.18
400 Hz 80.26 69.79 70.75 72.85 71.13 70.31 71.39 70.87 72.33 70.44 70.65
500 Hz 84.17 73.66 74.66 76.65 75.05 74.14 75.79 74.68 77.11 74.33 74.54
630 Hz 85.77 72.62 74.11 77.22 74.9 73.35 75.8 74.43 77.01 73.63 73.92
800 Hz 82.73 69.72 71.71 76.24 73.31 70.73 73 71.9 73.41 71.07 71.89
1000 Hz 81.96 70.02 72.04 76.76 74.18 71.03 72.74 72.13 73.41 71.59 72.83
1250 Hz 83.14 70.67 72.29 76.27 73.7 71.42 73.64 72.28 74.46 71.7 72.73
1600 Hz 84.8 71.48 73.2 77.43 74.72 72.26 74.64 73.1 75.03 72.44 73.57
2000 Hz 85.56 71.86 73.88 78.97 75.83 72.84 75.16 74.06 75.47 72.9 74.29
2500 Hz 84.68 69.88 71.99 77.81 73.87 70.88 72.99 72.15 73.65 71.09 72.39
3150 Hz 84.55 68.56 70.9 77.91 73.04 69.65 71.75 71.31 72.54 69.73 71.18
4000 Hz 82.01 65.6 68.08 75.56 70.87 66.72 68.82 68.54 69.32 66.77 68.58
5000 Hz 81.21 64.55 67 74.33 70.19 65.56 67.62 67.27 68.1 65.62 67.56
6300 Hz 80.17 63.42 65.56 73.05 68.63 64.02 66.57 65.49 66.54 64.2 66.08
8000 Hz 78.43 61.25 63.12 70.49 66.26 61.57 64.66 62.6 64.01 61.82 63.54
10000 Hz 77.68 59.93 61.19 67 62.86 60.02 63.84 60.42 62.84 60.15 61.01
Table 6.3-2 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-1 total SPL calculation at
listeners seats
Figure 6.3-9 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-1 total SPL calculation at
listeners seats
255
Scenario-2
Total sound pressure level (SPL) at the Coliseum redesign-2 setup-2 mapping at 1000 Hz for scenario-2 was
simulated in EASE (Fig 6.3-10). The overall sound pressure levels at each location of the Coliseum can be
interpreted from the mapping. Color scaled mapping can be useful to interpret uneven distribution of sound and
speaker system throughout the space. EASE calculated the sound pressure levels at 7 locations namely Student
section-1, Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The
results from the simulation are exported as a table with the overall peak, average and minimum sound pressure
values with the sound pressure levels for each location (Table 6.3-3) (Fig 6.3-11).
Figure 6.3-10 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-2 total SPL mapping at
1000 Hz
256
FREQUENCY
MAXIMUM (dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1 (dB)
STUDENT
SECTION-2 (dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1 (dB)
100 Hz 94.87 84.43 85.06 85.93 85.1 84.76 85.43 85.23 86.47 84.81 84.87
125 Hz 99.26 88.62 89.3 90.27 89.36 88.97 89.72 89.49 90.83 89.04 89.1
160 Hz 101.69 90.89 91.66 92.83 91.79 91.3 92.15 91.84 93.28 91.39 91.47
200 Hz 104.92 92.74 93.62 95.08 93.83 93.21 94.11 93.72 95.11 93.3 93.45
250 Hz 108.17 95.81 96.76 98.62 97.06 96.27 97.49 96.91 98.61 96.44 96.58
315 Hz 107.69 96.04 97.08 99.16 97.45 96.59 97.76 97.23 98.79 96.76 96.93
400 Hz 109.01 98.54 99.5 101.6 99.88 99.06 100.14 99.62 101.08 99.19 99.4
500 Hz 112.92 102.41 103.41 105.4 103.8 102.89 104.54 103.43 105.86 103.08 103.29
630 Hz 114.52 101.37 102.86 105.97 103.65 102.1 104.55 103.18 105.76 102.38 102.67
800 Hz 111.48 98.47 100.46 104.99 102.06 99.48 101.75 100.65 102.16 99.82 100.64
1000 Hz 110.71 98.77 100.79 105.51 102.93 99.78 101.49 100.88 102.16 100.34 101.58
1250 Hz 111.89 99.42 101.05 105.02 102.46 100.17 102.4 101.03 103.21 100.45 101.48
1600 Hz 113.55 100.23 101.95 106.18 103.47 101.01 103.39 101.85 103.78 101.19 102.32
2000 Hz 114.31 100.61 102.63 107.72 104.58 101.59 103.92 102.81 104.22 101.65 103.04
2500 Hz 113.43 98.63 100.74 106.56 102.62 99.63 101.74 100.9 102.4 99.84 101.15
3150 Hz 113.3 97.31 99.65 106.66 101.79 98.4 100.5 100.06 101.29 98.49 99.93
4000 Hz 110.76 94.35 96.83 104.31 99.62 95.47 97.57 97.3 98.07 95.52 97.33
5000 Hz 109.96 93.3 95.75 103.08 98.94 94.31 96.37 96.02 96.85 94.37 96.31
6300 Hz 108.92 92.17 94.31 101.8 97.39 92.77 95.32 94.24 95.29 92.95 94.83
8000 Hz 107.18 90 91.87 99.24 95.01 90.32 93.41 91.35 92.76 90.57 92.29
10000 Hz 106.43 88.68 89.94 95.75 91.61 88.77 92.59 89.17 91.59 88.9 89.76
Table 6.3-3 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-2 total SPL calculation at
listeners seats
Figure 6.3-11 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 scenario-2 total SPL calculation
at listeners seats
257
Setup-2
Los Angeles Memorial Coliseum redesign-2 setup-2 has a partial roof system over the north and south
audience stands with a reconfigured speaker system that is designed to focus on the audience from the partial roof
system (Fig 6.3-7).
Figure 6.3-12 Los Angeles Memorial Coliseum design modification-2 setup-2
Scenario-1
Total sound pressure level (SPL) at the Coliseum redesign-2 setup-2 mapping at 1000 Hz for scenario-1 was
simulated in EASE (Fig 6.3-13). The overall sound pressure levels at each location of the Coliseum can be
interpreted from the mapping. Color scaled mapping can be useful to interpret uneven distribution of sound and
speaker system throughout the space. EASE calculated the sound pressure levels at 7 locations namely Student
section-1, Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The
258
results from the simulation are exported as a table with the overall peak, average and minimum sound pressure
values with the sound pressure levels for each location (Table 6.3-4) (Fig 6.3-14).
Figure 6.3-13 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-1 total SPL mapping at
1000 Hz
259
FREQUENCY
MAXIMUM (dBA)
MINIMUM (dBA)
AVERAGE (dBA)
STUDENT
SECTION-1 (dB)
STUDENT
SECTION-2 (dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1 (dB)
TITANTRON-2 (dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1 (dB)
100 Hz 60 57.69 58.22 58.21 58.26 58.31 58.48 58.34 59.18 58.08 58.28
125 Hz 64.41 61.88 62.45 62.44 62.5 62.56 62.75 62.58 63.5 62.3 62.52
160 Hz 67.02 64.15 64.77 64.76 64.85 64.92 65.14 64.91 65.9 64.64 64.88
200 Hz 69.23 66.01 66.64 66.62 66.75 66.84 67.07 66.78 67.74 66.54 66.81
250 Hz 73.28 69.07 69.81 69.83 69.96 70 70.34 69.92 71.12 69.65 70.01
315 Hz 73.55 69.31 70.08 70.06 70.25 70.36 70.63 70.23 71.33 69.99 70.34
400 Hz 75.95 71.8 72.58 72.51 72.73 72.87 73.06 72.64 73.68 72.48 72.85
500 Hz 80.21 75.67 76.58 76.59 76.76 76.79 77.28 76.45 78.22 76.36 76.83
630 Hz 81.6 74.64 75.74 75.92 76.1 76.07 76.99 75.94 77.9 75.44 76.23
800 Hz 80.39 71.73 72.95 73.22 73.43 73.34 74.14 73.26 74.42 72.73 73.57
1000 Hz 79.25 72.03 73.3 73.64 73.85 73.69 74.02 73.5 74.46 73.16 73.53
1250 Hz 79.55 72.68 73.92 74.14 74.44 74.39 74.87 73.8 75.46 73.57 74.37
1600 Hz 81.86 73.49 74.78 75.02 75.32 75.29 75.81 74.6 76.06 74.37 75.41
2000 Hz 82.98 73.87 75.26 75.63 75.93 75.73 76.3 75.41 76.49 74.75 75.91
2500 Hz 82.1 71.89 73.35 73.84 73.91 73.84 74.16 73.47 74.62 72.85 74.02
3150 Hz 82.17 70.58 72.12 72.55 72.74 72.25 72.92 72.5 73.47 71.52 72.74
4000 Hz 79.51 67.61 69.2 69.86 69.9 69.49 69.97 69.69 70.29 68.51 69.88
5000 Hz 78.61 66.57 68.11 68.97 68.99 68.38 68.79 68.47 69.11 67.35 68.85
6300 Hz 77.54 65.44 66.83 67.58 67.56 67.21 67.74 66.87 67.66 66.06 67.39
8000 Hz 75.77 63.26 64.48 65.27 65.16 64.87 65.76 64.18 65.2 63.73 65.17
10000 Hz 73.94 61.95 62.84 63.13 63.65 63.3 64.8 62.27 64 62.2 63.4
Table 6.3-4 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-1 total SPL calculation at
listeners seats
Figure 6.3-14 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-1 total SPL calculation
at listeners seats
260
Scenario-2
Total sound pressure level (SPL) at the Coliseum redesign-2 setup-2 mapping at 1000 Hz for scenario-2 was
simulated in EASE (Fig 6.3-15). The overall sound pressure levels at each location of the Coliseum can be
interpreted from the mapping. Color scaled mapping can be useful to interpret uneven distribution of sound and
speaker system throughout the space. EASE calculated the sound pressure levels at 7 locations namely Student
section-1, Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The
results from the simulation are exported as a table with the overall peak, average and minimum sound pressure
values with the sound pressure levels for each location (Table 6.3-5) (Fig 6.3-16).
Figure 6.3-15 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-2 total SPL mapping at
1000 Hz
261
FREQUENCY
MAXIMUM (dBA)
MINIMUM (dBA)
AVERAGE (dBA)
STUDENT SECTION-
1 (dB)
STUDENT SECTION-
2 (dB)
GENERAL PUBLIC-1
(dB)
GENERAL PUBLIC-2
(dB)
TITANTRON-1 (dB)
TITANTRON-2 (dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1 (dB)
100 Hz 107.85 105.54 106.07 106.06 106.11 106.16 106.33 106.19 107.03 105.93 106.13
125 Hz 109.26 106.73 107.3 107.29 107.35 107.41 107.6 107.43 108.35 107.15 107.37
160 Hz 109.17 106.3 106.92 106.91 107 107.07 107.29 107.06 108.05 106.79 107.03
200 Hz 108.88 105.66 106.29 106.27 106.4 106.49 106.72 106.43 107.39 106.19 106.46
250 Hz 110.63 106.42 107.16 107.18 107.31 107.35 107.69 107.27 108.47 107 107.36
315 Hz 108.9 104.66 105.43 105.41 105.6 105.71 105.98 105.58 106.68 105.34 105.69
400 Hz 109.5 105.35 106.13 106.06 106.28 106.42 106.61 106.19 107.23 106.03 106.4
500 Hz 112.16 107.62 108.53 108.54 108.71 108.74 109.23 108.4 110.17 108.31 108.78
630 Hz 112.25 105.29 106.39 106.57 106.75 106.72 107.64 106.59 108.55 106.09 106.88
800 Hz 109.94 101.28 102.5 102.77 102.99 102.89 103.69 102.81 103.97 102.28 103.13
1000 Hz 108 100.78 102.05 102.39 102.6 102.44 102.77 102.25 103.21 101.92 102.28
1250 Hz 107.7 100.83 102.07 102.29 102.59 102.54 103.02 101.95 103.61 101.73 102.52
1600 Hz 109.61 101.24 102.53 102.77 103.07 103.04 103.56 102.35 103.81 102.12 103.16
2000 Hz 110.53 101.42 102.81 103.18 103.48 103.28 103.85 102.96 104.04 102.3 103.46
2500 Hz 109.55 99.34 100.8 101.29 101.36 101.29 101.61 100.93 102.07 100.3 101.47
3150 Hz 109.72 98.13 99.67 100.1 100.29 99.8 100.47 100.05 101.02 99.07 100.29
4000 Hz 107.26 95.36 96.95 97.61 97.65 97.24 97.72 97.44 98.04 96.26 97.63
5000 Hz 106.86 94.82 96.36 97.22 97.24 96.63 97.04 96.72 97.36 95.6 97.1
6300 Hz 106.39 94.29 95.68 96.43 96.41 96.06 96.59 95.72 96.51 94.91 96.24
8000 Hz 105.62 93.11 94.33 95.12 95.01 94.72 95.61 94.03 95.05 93.58 95.03
10000 Hz 105.19 93.2 94.09 94.38 94.9 94.55 96.05 93.52 95.25 93.45 94.65
Table 6.3-5 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-2 total SPL calculation at
listeners seats
Figure 6.3-16 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 scenario-2 total SPL calculation
at listeners seats
262
FIRST ARRIVAL
Setup-1
First arrival timing mapping calculates the arrival time for any location from the nearest sound source.
EASE calculated the first arrival timings at 7 locations namely Student section-1, Student section-2, General
audience-1, General audience-2, titantron, North-west corner, Away fans and exported as a table with overall peak,
average and minimum first arrival timings with the first arrival timings for each location (Table 6.3-6) (Fig 6.3-17).
Figure 6.3-17 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 first arrival mapping
First Arrival (ms)
Maximum
428.31
Minimum
0
Average
201.57
Student section-1
91.59
Student section-2
158.56
General Public-1
182.87
General Public-2
57.25
Titantron-1
73.98
Titantron-2
31.23
Southwest corner
126.7
Press Box-1
211.99
Table 6.3-6 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 first arrival calculation at listeners
seats
263
Setup-2
First arrival timing mapping calculates the arrival time for any location from the nearest sound source.
EASE calculated the first arrival timings at 7 locations namely Student section-1, Student section-2, General
audience-1, General audience-2, titantron, North-west corner, Away fans and exported as a table with the overall
peak, average and minimum first arrival timings for each location (Table 6.3-7) (Fig 6.3-18).
Figure 6.3-18 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 first arrival mapping
First Arrival (ms)
Maximum 228.92
Minimum 0.00
Average 152.19
Student section-1 135.95
Student section-2 135
General Public-1 140.17
General Public-2 57.25
Titantron-1 73.98
Titantron-2 31.23
Southwest corner 126.70
Press Box-1 128.98
Table 6.3-7 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 first arrival calculation at listeners
seats
264
C7
Setup-1
C7 is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct
sound field (ADA (Acoustic Design Anhert), 2009). Values above -15 dB are considered good. Values closer to 0
dB are considered better (ADA (Acoustic Design Anhert), 2009). C7 mapping at the Coliseum for 1000 Hz was
simulated in EASE (Fig 6.3-19). EASE calculated the C7 values at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum C7 values with the C7 values for
each location (Table 6.3-8) (Fig 6.3-20).
Figure 6.3-19 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C7 mapping at 1000 Hz
265
FREQUEN
CY
MAXIMUM
(dB)
MINIMUM
(dB)
AVERAGE
(dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1
(dB)
GENERAL
PUBLIC-2
(dB)
TITANTRO
N-1 (dB)
TITANTRO
N-2 (dB)
SOUTHWE
ST
CORNER
(dB)
PRESS
BOX-1 (dB)
100 Hz -30.31 -13.24 -4.7 -9.15 -17.1 -8.8 -11.82 -4.41 -13.86 -11.69 -30.31
125 Hz -30.12 -12.85 -4.15 -8.57 -16.86 -8.32 -11.52 -4.01 -13.41 -11.09 -30.12
160 Hz -29.84 -12.23 -3.22 -7.54 -16.45 -7.69 -11.29 -3.59 -12.8 -10.07 -29.84
200 Hz -29.1 -11.57 -2.26 -6.63 -15.99 -7.28 -11.5 -3.58 -12.49 -9.16 -29.1
250 Hz -31.21 -11.51 -1.01 -5.65 -17.19 -6.27 -11.31 -2.78 -11.94 -8.28 -31.21
315 Hz -31.1 -11.16 -0.27 -4.9 -16.01 -6.24 -11.1 -2.94 -11.61 -7.4 -31.1
400 Hz -30.84 -11.4 -0.25 -5 -15.92 -6.62 -11.7 -3.41 -12.25 -7.4 -30.84
500 Hz -32.09 -11.63 -0.31 -4.65 -17.59 -5.19 -12.36 -1.8 -11.65 -7.15 -32.09
630 Hz -33.78 -10.76 2.53 -2 -19.66 -2.82 -10.14 -0.29 -9.8 -5.24 -33.78
800 Hz -40.62 -11.17 5.16 0.68 -23.36 -2.75 -11.87 -2.35 -9.65 -2.48 -40.62
1000 Hz -38.43 -10.5 5.43 1.67 -21.63 -5.85 -13.36 -4.68 -9.74 -0.95 -38.43
1250 Hz -35.66 -10.57 3.98 -0.27 -19.46 -3.68 -13.48 -1.85 -10.87 -2.64 -35.66
1600 Hz -37.18 -10.84 4.47 0.15 -21.8 -2.78 -14.77 -2.39 -11.77 -2.53 -37.18
2000 Hz -40.01 -10.8 5.93 1.39 -22.17 -3.4 -14.04 -3.45 -11.22 -1.74 -40.01
2500 Hz -42.36 -11.37 6.95 1.47 -24.14 -3.16 -15.91 -3.11 -10.74 -1.48 -42.36
3150 Hz -44.92 -11.91 8.58 2.22 -27.05 -3.37 -16.83 -4.06 -11.6 -1.29 -44.92
4000 Hz -46.6 -11.92 9.3 3.48 -26.66 -3.77 -17.1 -5.53 -10.62 -0.44 -46.6
5000 Hz -49.7 -13 9.18 4.08 -30.26 -3.79 -17.38 -6.09 -10.6 -0.32 -49.7
6300 Hz -52.23 -13.71 9.08 3.58 -30.11 -2.47 -18.09 -4.86 -11.63 -0.87 -52.23
8000 Hz -59.27 -15.81 8.67 3.34 -33.33 -1.45 -17.82 -3.92 -12.31 -1.63 -59.27
10000 Hz -62.34 -17.74 6.11 -0.18 -32.4 0.45 -17.06 -1.31 -15.14 -5.51 -62.34
Table 6.3-8 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C7 calculation at listeners seats
Figure 6.3-20 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C7 calculation at listeners seats
266
Setup-2
C7 is ratio of direct and reverberant sound after 7 ms. It can be used to analyze the strength of the direct
sound field (ADA (Acoustic Design Anhert), 2009). Values above -15 dB are considered good. Values closer to 0
dB are considered better (ADA (Acoustic Design Anhert), 2009). C7 mapping at the Coliseum for 1000 Hz was
simulated in EASE (Fig 6.3-21). EASE calculated the C7 values at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum C7 values with the C7 values for
each location (Table 6.3-9) (Fig 6.3-22).
Figure 6.3-21 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C7 mapping at 1000 Hz
267
FREQUENCY
MAXIMUM (dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1 (dB)
STUDENT
SECTION-2 (dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz -2.98 -200 -16.2 -13.26 -13.09 -13.56 -10.8 -13.77 -6.29 -15.94 -15.9
125 Hz -2.47 -200 -15.73 -12.77 -12.55 -13.02 -10.31 -13.46 -5.89 -15.5 -15.37
160 Hz -1.61 -200 -15.16 -12.14 -11.79 -12.15 -9.67 -13.22 -5.46 -14.88 -14.6
200 Hz -0.8 -200 -14.75 -11.68 -11.11 -11.35 -9.25 -13.42 -5.45 -14.56 -13.73
250 Hz 0.27 -200 -13.72 -10.4 -10.02 -10.43 -8.18 -13.17 -4.58 -14 -12.42
315 Hz 0.66 -200 -13.46 -10.27 -9.47 -9.66 -8.18 -12.97 -4.77 -13.7 -11.93
400 Hz 0.33 -200 -13.15 -10.35 -9.22 -9.17 -8.58 -13.57 -5.26 -14.4 -11.4
500 Hz 1.09 -200 -12.18 -8.92 -8.32 -8.66 -7.04 -14.22 -3.51 -13.79 -10.8
630 Hz 4.36 -200 -11.69 -7.13 -7 -7.69 -4.52 -11.77 -1.88 -11.77 -9.23
800 Hz 6.56 -200 -11.71 -6 -5.93 -6.76 -4.4 -13.31 -3.84 -11.46 -8.13
1000 Hz 4.79 -200 -10.76 -5.31 -5.41 -6.37 -7.42 -14.78 -6.04 -11.46 -10.26
1250 Hz 4.26 -200 -10.14 -5.62 -5.15 -5.59 -5.34 -15.07 -3.4 -12.87 -8.73
1600 Hz 5.94 -200 -10.03 -5.24 -4.67 -5.03 -4.47 -16.31 -3.93 -13.81 -7.37
2000 Hz 6.38 -200 -9.79 -4.36 -3.84 -4.8 -4.97 -15.44 -4.86 -13.18 -6.88
2500 Hz 7.48 -200 -9.46 -3.82 -4.19 -4.74 -4.81 -17.27 -4.49 -12.62 -6.27
3150 Hz 9.13 -200 -9.23 -3.72 -3.72 -5.55 -4.99 -18.04 -5.31 -13.49 -5.76
4000 Hz 9.23 -200 -9.36 -2.74 -3.06 -4.71 -5.32 -18.27 -6.74 -12.48 -5.65
5000 Hz 9.4 -200 -9.83 -2.25 -2.43 -4.67 -5.38 -18.6 -7.31 -12.44 -5.5
6300 Hz 9.94 -200 -10.27 -2.65 -3.02 -4.38 -4.19 -19.49 -6.28 -13.6 -6.09
8000 Hz 10.51 -200 -11.12 -2.96 -3.35 -4.46 -3.2 -19.42 -5.51 -14.3 -6.32
10000 Hz 10.78 -200 -12.32 -5.53 -3.7 -4.88 -1.38 -18.93 -3.16 -17.24 -7.63
Table 6.3-9 Los Angeles Memorial Coliseum deign modification-2 EASE simulation setup-2 C7 calculation at listeners seats
Figure 6.3-22 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C7 calculation at listeners seats
268
C50
Setup-1
C50 measures the speech clarity which is the ratio between the early and late reflections in a space after 50
ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic
Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation (ADA
(Acoustic Design Anhert), 2009). C50 mapping at the Coliseum redesign-2 setup-1 for 1000 Hz was simulated in
EASE (Fig 6.3-23). EASE calculated the C50 values at 7 locations namely Student section-1, Student section-2,
General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation
are exported as a table with the overall peak, average and minimum C50 values with the C50 values for each
location (Table 6.3-10) (Fig 6.3-24).
Figure 6.3-23 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C50 mapping at 1000 Hz
269
FREQUENCY
MAXIMUM (dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1 (dB)
STUDENT
SECTION-2 (dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 9.63 -29.62 -9.3 -3.63 -6.94 -13.43 -5.76 -7.25 -2.31 -9.51 -8.41
125 Hz 9.85 -29.43 -8.94 -3.1 -6.44 -13.18 -5.32 -6.93 -1.9 -9.15 -7.94
160 Hz 10.04 -29.16 -8.45 -2.25 -5.64 -12.81 -4.82 -6.71 -1.57 -8.75 -7.25
200 Hz 11.4 -28.42 -7.93 -1.37 -4.91 -12.42 -4.55 -6.93 -1.73 -8.48 -6.61
250 Hz 11.69 -30.52 -7.83 -0.2 -4.1 -13.33 -3.59 -6.72 -0.85 -8.14 -5.96
315 Hz 11.08 -30.38 -7.47 0.51 -3.43 -12.35 -3.67 -6.57 -1.13 -7.88 -5.27
400 Hz 9.99 -30.11 -7.54 0.58 -3.42 -12.28 -3.86 -7 -1.45 -8 -5.16
500 Hz 10.22 -31.37 -7.53 0.58 -3.08 -13.53 -2.19 -7.35 0.51 -7.59 -4.89
630 Hz 13.11 -33.05 -6.76 3.23 -0.89 -14.95 -0.51 -5.6 1.32 -6.75 -3.52
800 Hz 13.08 -39.88 -6.54 5.76 1.51 -16.71 -1.48 -7.68 -1.44 -6.8 -1.3
1000 Hz 11.94 -37.69 -6.2 6.04 2.45 -15.84 -3.79 -9.13 -2.66 -6.92 0.04
1250 Hz 12.51 -34.94 -6.45 4.67 0.71 -14.56 -1.26 -8.56 -0.2 -7.15 -1.35
1600 Hz 13.44 -36.4 -6.49 5.18 1.14 -15.9 -0.88 -9.49 -0.86 -7.39 -1.2
2000 Hz 13.79 -39.2 -6.14 6.61 2.31 -15.92 -1.05 -9.23 -2.01 -7.03 -0.48
2500 Hz 15.01 -41.52 -6.13 7.66 2.46 -16.57 -1.28 -10.26 -1.76 -6.72 -0.17
3150 Hz 16.35 -44.05 -5.94 9.31 3.22 -17.01 -1.38 -11 -2.25 -6.83 0.1
4000 Hz 16.91 -45.61 -5.58 10.11 4.51 -16.71 -1.57 -11.03 -3.77 -6.07 0.97
5000 Hz 17.32 -48.6 -5.57 10.09 5.19 -16.68 -1.78 -10.78 -4.04 -5.66 1.23
6300 Hz 17.63 -50.92 -5.55 10.16 4.93 -15.68 -0.44 -10.2 -2.67 -5.3 1.04
8000 Hz 18.33 -57.66 -5.61 10.02 5.02 -14.69 0.88 -8.87 -1.39 -4.51 0.88
10000 Hz 21.46 -60.23 -5.72 8.01 2.62 -13.28 3.43 -6.96 1.52 -3.47 -0.75
Table 6.3-10 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C50 calculation at listeners seats
Figure 6.3-24 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C50 calculation at listeners seats
270
Setup-2
C50 measures the speech clarity which is the ratio between the early and late reflections in a space after 50
ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic
Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation (ADA
(Acoustic Design Anhert), 2009). C50 mapping at the Coliseum redesign-2 setup-2 for 1000 Hz was simulated in
EASE (Fig 6.3-25). EASE calculated the C50 values at 7 locations namely Student section-1, Student section-2,
General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation
are exported as a table with the overall peak, average and minimum C50 values with the C50 values for each
location (Table 6.3-11) (Fig 6.3-26).
Figure 6.3-25 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C50 mapping at 1000 Hz
271
FREQUENCY
MAXIMUM
(dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz -2 -18.57 -10.55 -9.48 -9.09 -8.44 -7.25 -8.92 -4.1 -14.02 -9.83
125 Hz -1.56 -18.01 -10.14 -9.06 -8.63 -8.01 -6.83 -8.6 -3.69 -13.63 -9.34
160 Hz -0.77 -17.5 -9.68 -8.56 -8 -7.4 -6.35 -8.37 -3.35 -13.13 -8.62
200 Hz 0.14 -17.28 -9.41 -8.18 -7.49 -6.85 -6.08 -8.52 -3.47 -12.84 -7.96
250 Hz 1.72 -17.17 -8.69 -7.32 -6.67 -6.33 -5.17 -8.27 -2.59 -12.4 -7.04
315 Hz 1.91 -16.69 -8.44 -7.13 -6.21 -5.72 -5.24 -8.12 -2.85 -12.13 -6.51
400 Hz 1.84 -16.83 -8.21 -7.12 -6.09 -5.47 -5.41 -8.47 -3.14 -12.55 -6.25
500 Hz 2.02 -17.2 -7.41 -6.08 -5.33 -5.13 -3.85 -8.73 -1.25 -12.05 -5.67
630 Hz 5.3 -17.3 -6.96 -4.63 -4 -4.24 -2.15 -7.01 -0.28 -10.56 -4.05
800 Hz 8.03 -21.66 -7.11 -3.81 -3.28 -3.82 -2.88 -8.67 -2.68 -10.34 -3.35
1000 Hz 6.41 -18.57 -6.39 -3.3 -2.93 -3.45 -4.94 -9.89 -3.76 -10.34 -4.65
1250 Hz 5.6 -18.32 -6.02 -3.59 -2.8 -3.01 -2.75 -9.48 -1.63 -11.31 -3.58
1600 Hz 7.57 -20.31 -5.92 -3.23 -2.5 -2.73 -2.37 -10.16 -2.2 -11.89 -2.73
2000 Hz 8.4 -21.45 -5.79 -2.57 -1.97 -2.63 -2.43 -9.85 -3.12 -11.37 -2.49
2500 Hz 9.83 -23.91 -5.57 -2.01 -2.01 -2.25 -2.63 -10.62 -2.83 -10.91 -2.25
3150 Hz 11.49 -26.48 -5.29 -1.79 -1.54 -2.88 -2.66 -11.07 -3.17 -11.35 -2.03
4000 Hz 11.96 -26.85 -5.25 -0.98 -1.12 -2.21 -2.73 -10.98 -4.44 -10.48 -1.71
5000 Hz 12.28 -30.71 -5.37 -0.41 -0.62 -2.13 -2.86 -10.68 -4.63 -10.24 -1.5
6300 Hz 12.53 -29.33 -5.42 -0.62 -0.93 -1.72 -1.7 -10.06 -3.45 -10.55 -2.04
8000 Hz 13.18 -32.83 -5.48 -0.52 -1.07 -1.53 -0.44 -8.83 -2.3 -10.29 -1.84
10000 Hz 12.98 -30.65 -5.6 -1.81 -0.99 -1.3 1.86 -7.12 0.2 -10.27 -2.7
Table 6.3-11 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C50 calculation at listeners seats
Figure 6.3-26 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C50 calculation at listeners seats
272
C80
Setup-1
C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space. C80 mapping at the Coliseum redesign-2 setup-1 for 1000 Hz was
simulated in EASE (Fig 6.3-27). EASE calculated the C80 values at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum C80 values with the C80 values for
each location (Table 6.3-12) (Fig 6.3-28).
Figure 6.3-27 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C80 mapping at 1000 Hz
273
FREQUENCY
MAXIMUM
(dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz 9.99 -23.05 -6.37 -2.53 -5.09 -8.58 -4.25 -5.32 -1.4 -6.78 -6.08
125 Hz 10.23 -22.75 -6 -2.01 -4.63 -8.29 -3.82 -4.99 -0.99 -6.43 -5.65
160 Hz 10.44 -22.21 -5.55 -1.22 -3.95 -7.99 -3.37 -4.76 -0.65 -6.09 -5.09
200 Hz 11.81 -21.66 -5.09 -0.4 -3.32 -7.69 -3.1 -4.83 -0.75 -5.82 -4.57
250 Hz 12.13 -22.89 -4.83 0.69 -2.62 -7.89 -2.28 -4.65 0.06 -5.54 -4.01
315 Hz 11.56 -22.22 -4.46 1.4 -2.01 -7.41 -2.3 -4.47 -0.16 -5.3 -3.42
400 Hz 10.52 -22.26 -4.43 1.52 -1.91 -7.19 -2.38 -4.66 -0.38 -5.25 -3.24
500 Hz 10.8 -23.57 -4.26 1.58 -1.56 -7.43 -0.95 -4.78 1.42 -4.88 -2.95
630 Hz 13.68 -24.85 -3.43 4.05 0.29 -7.97 0.45 -3.76 2.09 -4.42 -1.9
800 Hz 13.68 -26.47 -2.78 6.47 2.44 -8.54 -0.51 -5.48 -0.55 -4.57 -0.07
1000 Hz 12.56 -25.24 -2.59 6.76 3.33 -8.28 -2.53 -6.39 -1.64 -4.73 1.13
1250 Hz 13.15 -25.31 -2.94 5.48 1.8 -7.58 -0.17 -5.68 0.71 -4.57 -0.01
1600 Hz 14.1 -27.29 -2.76 6.02 2.24 -7.72 0.21 -6.14 0.15 -4.6 0.19
2000 Hz 14.48 -27.03 -2.26 7.43 3.35 -7.7 0.05 -6.2 -0.94 -4.29 0.86
2500 Hz 15.77 -27.99 -1.99 8.52 3.56 -7.56 -0.05 -6.68 -0.68 -4.03 1.22
3150 Hz 17.16 -28.83 -1.49 10.2 4.35 -7.37 -0.09 -7.16 -1.13 -3.93 1.56
4000 Hz 17.83 -31.07 -0.96 11.09 5.68 -6.92 -0.18 -7.05 -2.37 -3.18 2.47
5000 Hz 18.36 -33.72 -0.59 11.2 6.46 -6.39 -0.22 -6.53 -2.44 -2.64 2.85
6300 Hz 18.85 -35.85 -0.28 11.47 6.45 -5.16 1.24 -5.39 -0.89 -1.9 2.99
8000 Hz 19.84 -41.12 0.28 11.64 6.89 -3.78 2.75 -3.61 0.74 -0.74 3.29
10000 Hz 23.43 -44.82 0.61 10.21 5.36 -2.03 5.84 -1 4.15 0.94 2.76
Table 6.3-12 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C80 calculation at listeners seats
Figure 6.3-28 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 C80 calculation at listeners seats
274
Setup-2
C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space. C80 mapping at the Coliseum redesign-2 setup-2 for 1000 Hz was
simulated in EASE (Fig 6.3-29). EASE calculated the C80 values at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum C80 values with the C80 values for
each location (Table 6.3-13) (Fig 6.3-30).
Figure 6.3-29 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C80 mapping at 1000 Hz
275
FREQUENCY
MAXIMUM
(dB)
MINIMUM (dB)
AVERAGE (dB)
STUDENT
SECTION-1
(dB)
STUDENT
SECTION-2
(dB)
GENERAL
PUBLIC-1 (dB)
GENERAL
PUBLIC-2 (dB)
TITANTRON-1
(dB)
TITANTRON-2
(dB)
SOUTHWEST
CORNER (dB)
PRESS BOX-1
(dB)
100 Hz -1.13 -13.07 -6.93 -6.51 -6.28 -6.14 -5.37 -6.44 -2.94 -8.58 -6.69
125 Hz -0.72 -12.56 -6.55 -6.12 -5.86 -5.74 -4.97 -6.12 -2.53 -8.23 -6.26
160 Hz 0.04 -11.85 -6.15 -5.68 -5.34 -5.23 -4.55 -5.87 -2.19 -7.85 -5.7
200 Hz 0.93 -11.22 -5.84 -5.32 -4.89 -4.75 -4.28 -5.86 -2.23 -7.51 -5.16
250 Hz 2.41 -10.1 -5.34 -4.69 -4.27 -4.31 -3.54 -5.64 -1.46 -7.17 -4.49
315 Hz 2.64 -10.01 -5.04 -4.45 -3.84 -3.8 -3.54 -5.47 -1.63 -6.84 -4.01
400 Hz 2.61 -10.28 -4.8 -4.37 -3.68 -3.52 -3.58 -5.54 -1.81 -6.62 -3.76
500 Hz 2.77 -9.18 -4.25 -3.58 -3.08 -3.19 -2.31 -5.55 -0.13 -6.27 -3.3
630 Hz 5.9 -8.68 -3.81 -2.43 -1.99 -2.53 -0.94 -4.63 0.68 -6.01 -2.05
800 Hz 8.66 -10.13 -3.68 -1.87 -1.46 -2.2 -1.62 -5.84 -1.51 -5.87 -1.53
1000 Hz 7.1 -10.73 -3.32 -1.48 -1.13 -1.86 -3.3 -6.49 -2.41 -5.82 -2.41
1250 Hz 6.29 -8.9 -3.08 -1.63 -1.02 -1.41 -1.37 -5.95 -0.47 -5.6 -1.6
1600 Hz 8.26 -9.42 -2.86 -1.31 -0.74 -1.12 -1 -6.17 -0.9 -5.44 -0.92
2000 Hz 9.1 -10.07 -2.61 -0.72 -0.23 -0.97 -1.03 -6.16 -1.72 -5.24 -0.64
2500 Hz 10.58 -10.11 -2.27 -0.16 -0.12 -0.56 -1.08 -6.4 -1.4 -4.95 -0.3
3150 Hz 12.31 -11.4 -1.88 0.12 0.34 -0.91 -1.03 -6.63 -1.68 -4.86 -0.05
4000 Hz 12.87 -11.72 -1.48 0.96 0.87 -0.2 -0.97 -6.42 -2.59 -4.28 0.39
5000 Hz 13.31 -11.92 -1.22 1.61 1.44 0.05 -0.9 -5.88 -2.55 -4.06 0.72
6300 Hz 13.74 -11.29 -0.81 1.72 1.49 0.72 0.35 -4.81 -1.19 -3.54 0.65
8000 Hz 14.67 -10.22 -0.21 2.24 1.85 1.37 1.79 -3.19 0.3 -2.71 1.29
10000 Hz 14.9 -11.73 0.54 2.07 2.62 2.34 4.54 -0.91 3.21 -1.34 1.52
Table 6.3-13 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C80 calculation at listeners seats
Figure 6.3-30 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 C80 calculation at listeners seats
276
Articulation loss of consonants
Setup-1
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable. EASE calculated the AL cons at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans and exported as a table
with the overall peak, average and minimum AL cons percentages for each location (Table 6.3-14) (Fig 6.3-31).
Figure 6.3-31 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 Articulation loss of consonants
mapping
Articulation Loss of Consonants (ALC) (%)
Maximum
100
Minimum
1.04
Average
14.12
Student section-1
3.12
Student section-2
6.35
General Public-1
24.26
General Public-2
10.79
Titantron-1
18.74
Titantron-2
10.8
Southwest corner
19.26
Press Box-1
9.37
Table 6.3-14 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 Articulation loss of consonants
calculation at listeners seats
277
Setup-2
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable. EASE calculated the AL cons at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans and exported as a table
with the overall peak, average and minimum AL cons percentages for each location (Table 6.3-15) (Fig 6.3-32).
Figure 6.3-32 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 Articulation loss of consonants
mapping
Articulation Loss of Consonants (ALC) (%)
Maximum
100
Minimum
2.52
Average
14.41
Student section-1
11.54
Student section-2
11.17
General Public-1
12.15
General Public-2
12.72
Titantron-1
20.53
Titantron-2
12.48
Southwest corner
21.65
Press Box-1
11.34
Table 6.3-15 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 Articulation loss of consonants
calculation at listeners seats
278
Speech transmission index
Setup-1
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable. EASE calculated the speech transmission index at 7 locations namely Student section-1,
Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans and exported as
a table with the overall peak, average and minimum values for each location (Table 6.3-16) (Fig 6.3-33).
Figure 6.3-33 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 Speech Transmission Index
mapping
Speech Transmission Index (STI)
Maximum
0.94
Minimum
0
Average
0.535
Student section-1
0.738
Student section-2
0.607
General Public-1
0.36
General Public-2
0.509
Titantron-1
0.408
Titantron-2
0.509
Southwest corner
0.402
Press Box-1
0.535
Table 6.3-16 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-1 Speech Transmission Index
calculation at listeners seats
279
Setup-2
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009). EASE calculated the speech transmission index
at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron,
North-west corner, Away fans. The results from the simulation are exported as a table with the overall peak, average
and minimum speech transmission index for each location (Table 4.3-17) (Fig 4.3-34).
Figure 6.3-34 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 Speech Transmission Index
mapping
Speech Transmission Index (STI)
Maximum
0.778
Minimum
0
Average
0.462
Student section-1
0.497
Student section-2
0.503
General Public-1
0.487
General Public-2
0.479
Titantron-1
0.391
Titantron-2
0.482
Southwest corner
0.381
Press Box-1
0.5
Table 6.3-17 Los Angeles Memorial Coliseum design modification-2 EASE simulation setup-2 Speech Transmission Index
calculation at listeners seats
280
6.4 Discussion
The results from EASE simulations of the two proposed retrofits are described in the previous sections.
Two scenarios were considered while simulating the acoustic conditions of the Coliseum. The input for ambient
noise varied in both the scenarios which are taken from the field study data collected at the Coliseum during the
2017 football season.
Scenario-1 data was collected during play. Scenario-2 input data was based on the peak noise levels
measured during in game scenarios (USC Trojans Touchdown, Sack etc.) favoring the home team which bring the
loudest response from the audience (Table 5.3-15). Two sets of simulation results are described based on each
scenario. The same input data will be used for the EASE simulations of the design modification analysis of the
Coliseum. Scenario-2 will have all the speaker sound pressure levels increased by 15 decibels. All mappings of the
Coliseum shown in results are based on 1000 Hz frequency (Fig 5.3-15). However, several listener seats were
placed in the model similar to the locations used for collecting data at the Coliseum. All listeners seats will have
results from Octave bandwidth range (100 Hz – 10000 Hz).
Figure 6.4-1 Los Angeles Memorial Coliseum design modification analysis methodology overview
6.4.1 Total SPL
Total sound pressure level (SPL) at the Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1,
Coliseum redesign setup-2 mapping at 1000 Hz for scenario-1 and scenario-2 was simulated in EASE (Fig 6.4-2)
(Fig 6.4-3). The overall sound pressure levels at each location of the Coliseum can be interpreted from the mapping.
Color scaled mapping can be useful to interpret uneven distribution of sound and speaker system throughout the
space. EASE calculated the sound pressure levels at 7 locations namely Student section-1, Student section-2,
281
General audience-1, General audience-2, titantron, North-west corner, Away fans. The results are sorted based on
location to draw a comparison form existing conditions to the new proposed retrofit.
Total sound pressure level (SPL) mapping at 1000 Hz for scenario-1 at the student section-1, student
section-2 from EASE simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum
redesign setup-2 were grouped together to draw comparison. EASE simulation results show that the Coliseum
redesign-2 setup-2 with the reconfigured speaker system have higher SPL levels compared to the existing Coliseum.
Coliseum redesign-1 had higher SPL values than the existing Coliseum due to the presence of the enlarged glass box
in the press box which reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof
system which was designed to contain the sound and reflect it within the stadium which resulted in higher SPL
values (Table 6.4-1).
Frequency
Student section-1 Student section-2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 56.79 61.18 57.18 58.21 57.33 60.87 56.35 58.26
125 Hz 60.7 65.36 61.52 62.44 61.35 65.01 60.61 62.5
160 Hz 62.33 67.38 64.08 64.76 63.19 66.92 63.04 64.85
200 Hz 63.67 69.12 66.33 66.62 64.68 68.51 65.08 66.75
250 Hz 66.2 72.17 69.87 69.83 67.7 71.32 68.31 69.96
315 Hz 66.04 72.45 70.41 70.06 67.61 71.46 68.7 70.25
400 Hz 67.96 74.8 72.85 72.51 69.58 73.77 71.13 72.73
500 Hz 71.28 78.51 76.65 76.59 73.96 77.54 75.05 76.76
630 Hz 70.71 78.49 77.22 75.92 74.33 76.88 74.9 76.1
800 Hz 68.53 77.04 76.24 73.22 71.52 74.75 73.31 73.43
1000 Hz 68.75 77.46 76.76 73.64 70.92 75.37 74.18 73.85
1250 Hz 68.52 77.18 76.27 74.14 71.89 75.23 73.7 74.44
1600 Hz 69.52 78.31 77.43 75.02 73 76.23 74.72 75.32
2000 Hz 70.68 79.66 78.97 75.63 73.64 77.14 75.83 75.93
2500 Hz 69.03 78.37 77.81 73.84 71.48 75.16 73.87 73.91
3150 Hz 68.28 78.31 77.91 72.55 70.41 74.16 73.04 72.74
4000 Hz 65.64 75.88 75.56 69.86 67.64 71.76 70.87 69.9
5000 Hz 64.49 74.6 74.33 68.97 66.46 70.87 70.19 68.99
6300 Hz 62.49 73.27 73.05 67.58 65.51 69.22 68.63 67.56
8000 Hz 59.81 70.67 70.49 65.27 63.77 66.72 66.26 65.16
10000 Hz 57.95 67.22 67 63.13 63.08 63.41 62.86 63.65
Table 6.4-1 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 at student section- 1, student
section- 2
282
Total sound pressure level (SPL) mapping at 1000 Hz for scenario-2 at the student section-1, student
section-2 from EASE simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum
redesign setup-2 were grouped together to draw comparison. EASE simulation results show that the Coliseum
redesign-2 setup-2 with the reconfigured speaker system have higher SPL levels compared to the existing Coliseum.
Coliseum redesign-1 had higher SPL values than the existing Coliseum due to the presence of the enlarged glass box
in the press box which reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof
system, which was designed to contain the sound and reflect it within the stadium which resulted in higher SPL
values (Table 6.4-2).
Frequency
Student section-1 Student section-2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 85.85 76.18 85.93 106.06 85 75.87 85.1 106.11
125 Hz 89.97 80.36 90.27 107.29 88.99 80.01 89.36 107.35
160 Hz 92.08 82.38 92.83 106.91 90.81 81.92 91.79 107
200 Hz 94.06 84.12 95.08 106.27 92.41 83.51 93.83 106.4
250 Hz 97.44 87.17 98.62 107.18 95.26 86.32 97.06 107.31
315 Hz 97.85 87.45 99.16 105.41 95.33 86.46 97.45 105.6
400 Hz 100.08 89.8 101.6 106.06 97.36 88.77 99.88 106.28
500 Hz 103.67 93.51 105.4 108.54 100.99 92.54 103.8 108.71
630 Hz 104.77 93.49 105.97 106.57 101.35 91.88 103.65 106.75
800 Hz 104.23 92.04 104.99 102.77 100.4 89.75 102.06 102.99
1000 Hz 104.76 92.46 105.51 102.39 101.45 90.37 102.93 102.6
1250 Hz 104.01 92.18 105.02 102.29 100.42 90.23 102.46 102.59
1600 Hz 105.28 93.31 106.18 102.77 101.58 91.23 103.47 103.07
2000 Hz 107.05 94.66 107.72 103.18 103.06 92.14 104.58 103.48
2500 Hz 106.04 93.37 106.56 101.29 101.19 90.16 102.62 101.36
3150 Hz 106.31 93.31 106.66 100.1 100.6 89.16 101.79 100.29
4000 Hz 104.02 90.88 104.31 97.61 98.73 86.76 99.62 97.65
5000 Hz 102.8 89.6 103.08 97.22 98.17 85.87 98.94 97.24
6300 Hz 101.53 88.27 101.8 96.43 96.58 84.22 97.39 96.41
8000 Hz 98.96 85.67 99.24 95.12 94.23 81.72 95.01 95.01
10000 Hz 95.29 82.22 95.75 94.38 90.31 78.41 91.61 94.9
Table 6.4-2 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 at student section- 1, student
section- 2
Total sound pressure level (SPL) mapping at 1000 Hz for scenario-1 at the general public-1, general public-
2 from EASE simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign
setup-2 were grouped together to draw comparison. EASE simulation results show that the Coliseum redesign-2
283
setup-2 with the reconfigured speaker system have higher SPL levels compared to the existing Coliseum. Coliseum
redesign-1 had higher SPL values than the existing Coliseum due to the presence of the enlarged glass box in the
press box which reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof system that
was designed to contain the sound and reflect it within the stadium which resulted in higher SPL values (Table 6.4-
3).
Frequency
General Public- 1 General Public- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 57.16 60.75 56.01 58.31 58.24 60.99 56.68 58.48
125 Hz 61.13 64.88 60.22 62.56 62.37 65.15 60.97 62.75
160 Hz 62.85 66.73 62.55 64.92 64.36 67.07 63.4 65.14
200 Hz 64.2 68.24 64.46 66.84 65.82 68.64 65.36 67.07
250 Hz 66.94 70.94 67.52 70 69.07 71.54 68.74 70.34
315 Hz 66.84 71.03 67.84 70.36 68.96 71.63 69.01 70.63
400 Hz 68.75 73.35 70.31 72.87 70.93 73.92 71.39 73.06
500 Hz 72.1 77.05 74.14 76.79 75.82 77.97 75.79 77.28
630 Hz 72.23 75.97 73.35 76.07 75.92 77.48 75.8 76.99
800 Hz 69.82 73.06 70.73 73.34 72.03 74.53 73 74.14
1000 Hz 69.87 73.21 71.03 73.69 71.82 74.32 72.74 74.02
1250 Hz 69.57 73.75 71.42 74.39 73.01 75.19 73.64 74.87
1600 Hz 70.47 74.65 72.26 75.29 73.5 76.17 74.64 75.81
2000 Hz 71.89 75.15 72.84 75.73 73.99 76.66 75.16 76.3
2500 Hz 70.17 73.15 70.88 73.84 72.33 74.52 72.99 74.16
3150 Hz 69.74 71.81 69.65 72.25 71.4 73.2 71.75 72.92
4000 Hz 67.21 68.74 66.72 69.49 68.22 70.17 68.82 69.97
5000 Hz 65.95 67.3 65.56 68.38 67.03 68.78 67.62 68.79
6300 Hz 64.06 65.54 64.02 67.21 65.45 67.48 66.57 67.74
8000 Hz 61.06 62.82 61.57 64.87 62.95 65.32 64.66 65.76
10000 Hz 58.54 61.02 60.02 63.3 61.86 64.28 63.84 64.8
Table 6.4-3 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 at general public- 1, general
public- 2
Total sound pressure level (SPL) 2 mapping at 1000 Hz for scenario-2 at the general public-1, general
public-2 from EASE simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum
redesign setup-2 were grouped together to draw comparison. EASE simulation results show that the Coliseum
redesign-2 setup-2 with the reconfigured speaker system have higher SPL levels compared to the existing Coliseum.
Coliseum redesign-1 had higher SPL values than the existing Coliseum due to the presence of the enlarged glass box
in the press box which reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof
284
system which was designed to contain the sound and reflect it within the stadium which resulted in higher SPL
values (Table 6.4-4).
Frequency
General Public- 1 General Public- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 84.65 75.75 84.76 106.16 85.34 75.99 85.43 106.33
125 Hz 88.56 79.88 88.97 107.41 89.38 80.15 89.72 107.6
160 Hz 90.19 81.73 91.3 107.07 91.26 82.07 92.15 107.29
200 Hz 91.52 83.24 93.21 106.49 92.79 83.64 94.11 106.72
250 Hz 94.01 85.94 96.27 107.35 95.9 86.54 97.49 107.69
315 Hz 93.84 86.03 96.59 105.71 95.83 86.63 97.76 105.98
400 Hz 95.76 88.35 99.06 106.42 97.81 88.92 100.14 106.61
500 Hz 99.04 92.05 102.89 108.74 102.31 92.97 104.54 109.23
630 Hz 98.26 90.97 102.1 106.72 102.79 92.48 104.55 107.64
800 Hz 95.76 88.06 99.48 102.89 99.93 89.53 101.75 103.69
1000 Hz 95.82 88.21 99.78 102.44 99.24 89.32 101.49 102.77
1250 Hz 95.82 88.75 100.17 102.54 100.33 90.19 102.4 103.02
1600 Hz 96.8 89.65 101.01 103.04 101.45 91.17 103.39 103.56
2000 Hz 97.73 90.15 101.59 103.28 102.08 91.66 103.92 103.85
2500 Hz 96.06 88.15 99.63 101.29 99.9 89.52 101.74 101.61
3150 Hz 95.2 86.81 98.4 99.8 98.82 88.2 100.5 100.47
4000 Hz 92.59 83.74 95.47 97.24 96.03 85.17 97.57 97.72
5000 Hz 91.54 82.3 94.31 96.63 94.86 83.78 96.37 97.04
6300 Hz 89.86 80.54 92.77 96.06 93.94 82.48 95.32 96.59
8000 Hz 87.45 77.82 90.32 94.72 92.24 80.32 93.41 95.61
10000 Hz 85.79 76.02 88.77 94.55 91.58 79.28 92.59 96.05
Table 6.4-4 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 at general public- 1, general
public- 2
Total sound pressure level (SPL) mapping at 1000 Hz for scenario-1 at the Titantron-1, Titantron-2 from
EASE simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were
grouped together to draw comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the
reconfigured speaker system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had
higher SPL values than the existing Coliseum due to the presence of the enlarged glass box in the press box which
reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed
to contain the sound and reflect it within the stadium which resulted in higher SPL values (Table 6.4-5).
285
Frequency
Titantron- 1 Titantron- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 56.81 60.92 56.48 58.34 56.85 61.41 57.72 59.18
125 Hz 60.72 65.06 60.74 62.58 60.77 65.6 62.08 63.5
160 Hz 62.37 66.94 63.09 64.91 62.43 67.59 64.53 65.9
200 Hz 63.7 68.46 64.97 66.78 63.84 69.14 66.36 67.74
250 Hz 66.29 71.25 68.16 69.92 66.41 72.17 69.86 71.12
315 Hz 66.12 71.35 68.48 70.23 66.28 72.22 70.04 71.33
400 Hz 68.01 73.63 70.87 72.64 68.24 74.47 72.33 73.68
500 Hz 71.42 77.33 74.68 76.45 71.64 78.82 77.11 78.22
630 Hz 70.75 76.6 74.43 75.94 71.09 78.33 77.01 77.9
800 Hz 68.26 73.79 71.9 73.26 69.4 74.82 73.41 74.42
1000 Hz 68.81 73.9 72.13 73.5 70.4 74.79 73.41 74.46
1250 Hz 68.34 74.27 72.28 73.8 69.78 75.77 74.46 75.46
1600 Hz 69.05 75.16 73.1 74.6 70.73 76.45 75.03 76.06
2000 Hz 69.65 75.91 74.06 75.41 71.8 76.88 75.47 76.49
2500 Hz 68.3 73.94 72.15 73.47 69.94 74.99 73.65 74.62
3150 Hz 67.16 72.89 71.31 72.5 69.06 73.78 72.54 73.47
4000 Hz 64.49 69.97 68.54 69.69 66.84 70.55 69.32 70.29
5000 Hz 63.48 68.51 67.27 68.47 65.92 69.15 68.1 69.11
6300 Hz 62.11 66.63 65.49 66.87 64.49 67.46 66.54 67.66
8000 Hz 59.9 63.61 62.6 64.18 62.04 64.77 64.01 65.2
10000 Hz 58.13 61.34 60.42 62.27 59.16 63.39 62.84 64
Table 6.4-5 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 at Titantron- 1, Titantron- 2
Total sound pressure level (SPL) 2 mapping at 1000 Hz for scenario-2 at the Titantron-1, Titantron-2 from
EASE simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were
grouped together to draw comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the
reconfigured speaker system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had
higher SPL values than the existing Coliseum due to the presence of the enlarged glass box in the press box which
reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed
to contain the sound and reflect it within the stadium which resulted in higher SPL values (Table 6.4-6).
286
Frequency
Titantron- 1 Titantron- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 85.14 75.92 85.23 106.19 86.4 76.41 86.47 107.03
125 Hz 89.12 80.06 89.49 107.43 90.56 80.6 90.83 108.35
160 Hz 90.88 81.94 91.84 107.06 92.61 82.59 93.28 108.05
200 Hz 92.25 83.46 93.72 106.43 94.1 84.14 95.11 107.39
250 Hz 95.04 86.25 96.91 107.27 97.44 87.17 98.61 108.47
315 Hz 94.97 86.35 97.23 105.58 97.35 87.22 98.79 106.68
400 Hz 96.88 88.63 99.62 106.19 99.32 89.47 101.08 107.23
500 Hz 100.24 92.33 103.43 108.4 104.34 93.82 105.86 110.17
630 Hz 100.53 91.6 103.18 106.59 104.49 93.33 105.76 108.55
800 Hz 98.14 88.79 100.65 102.81 100.55 89.82 102.16 103.97
1000 Hz 98.16 88.9 100.88 102.25 100.31 89.79 102.16 103.21
1250 Hz 97.84 89.27 101.03 101.95 101.57 90.77 103.21 103.61
1600 Hz 98.74 90.16 101.85 102.35 102.05 91.45 103.78 103.81
2000 Hz 100.26 90.91 102.81 102.96 102.53 91.88 104.22 104.04
2500 Hz 98.54 88.94 100.9 100.93 100.87 89.99 102.4 102.07
3150 Hz 98.15 87.89 100.06 100.05 99.94 88.78 101.29 101.02
4000 Hz 95.63 84.97 97.3 97.44 96.73 85.55 98.07 98.04
5000 Hz 94.36 83.51 96.02 96.72 95.52 84.15 96.85 97.36
6300 Hz 92.39 81.63 94.24 95.72 93.91 82.46 95.29 96.51
8000 Hz 89.27 78.61 91.35 94.03 91.36 79.77 92.76 95.05
10000 Hz 86.55 76.34 89.17 93.52 90.28 78.39 91.59 95.25
Table 6.4-6 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 at Titantron- 1, Titantron- 2
Total sound pressure level (SPL) mapping at 1000 Hz for scenario-1 at the Southwest corner, Pressbox-1
from EASE simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2
were grouped together to draw comparison. EASE simulation results show that the Coliseum redesign-2 setup-2
with the reconfigured speaker system have higher SPL levels compared to the existing Coliseum. Coliseum
redesign-1 had higher SPL values than the existing Coliseum due to the presence of the enlarged glass box in the
press box which reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof system that
was designed to contain the sound and reflect it within the stadium which resulted in higher SPL values (Table 6.4-
7).
287
Frequency
Southwest corner Press box- 1
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 57.11 60.77 56.06 58.08 58.4 60.87 56.12 58.28
125 Hz 61.06 64.9 60.29 62.3 62.57 65.01 60.35 62.52
160 Hz 62.79 66.76 62.64 64.64 64.82 66.92 62.72 64.88
200 Hz 64.25 68.28 64.55 66.54 66.87 68.51 64.7 66.81
250 Hz 66.92 71.02 67.69 69.65 70.25 71.32 67.83 70.01
315 Hz 66.82 71.11 68.01 69.99 70.82 71.46 68.18 70.34
400 Hz 68.76 73.41 70.44 72.48 73.11 73.77 70.65 72.85
500 Hz 72.22 77.15 74.33 76.36 76.65 77.54 74.54 76.83
630 Hz 71.84 76.13 73.63 75.44 77.46 76.88 73.92 76.23
800 Hz 69.73 73.26 71.07 72.73 76.74 74.75 71.89 73.57
1000 Hz 70.09 73.55 71.59 73.16 77.6 75.37 72.83 73.53
1250 Hz 69.9 73.92 71.7 73.57 76.88 75.23 72.73 74.37
1600 Hz 70.88 74.76 72.44 74.37 77.93 76.23 73.57 75.41
2000 Hz 71.88 75.18 72.9 74.75 79.25 77.14 74.29 75.91
2500 Hz 70.27 73.28 71.09 72.85 78.34 75.16 72.39 74.02
3150 Hz 69.52 71.86 69.73 71.52 78.41 74.16 71.18 72.74
4000 Hz 66.98 68.77 66.77 68.51 75.89 71.76 68.58 69.88
5000 Hz 65.96 67.34 65.62 67.35 74.66 70.87 67.56 68.85
6300 Hz 64.42 65.66 64.2 66.06 73.51 69.22 66.08 67.39
8000 Hz 61.93 63.01 61.82 63.73 70.9 66.72 63.54 65.17
10000 Hz 59.64 61.13 60.15 62.2 67.64 63.41 61.01 63.4
Table 6.4-7 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 at Southwest corner, Press
box-1
Total sound pressure level (SPL) mapping at 1000 Hz for scenario-2 at the Southwest corner, Pressbox-1
from EASE simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2
were grouped together to draw comparison. EASE simulation results show that the Coliseum redesign-2 setup-2
with the reconfigured speaker system have higher SPL levels compared to the existing Coliseum. Coliseum
redesign-1 had higher SPL values than the existing Coliseum due to the presence of the enlarged glass box in the
press box which reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof system
which was designed to contain the sound and reflect it within the stadium which resulted in higher SPL values
(Table 6.4-8).
288
Frequency
Southwest corner Press box- 1
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 84.71 75.77 84.81 105.93 84.71 75.79 84.87 106.13
125 Hz 88.64 79.9 89.04 107.15 88.64 79.92 89.1 107.37
160 Hz 90.31 81.76 91.39 106.79 90.33 81.79 91.47 107.03
200 Hz 91.66 83.28 93.3 106.19 91.76 83.34 93.45 106.46
250 Hz 94.28 86.02 96.44 107 94.37 86.08 96.58 107.36
315 Hz 94.15 86.11 96.76 105.34 94.26 86.19 96.93 105.69
400 Hz 96.03 88.41 99.19 106.03 96.24 88.51 99.4 106.4
500 Hz 99.48 92.15 103.08 108.31 99.71 92.25 103.29 108.78
630 Hz 98.92 91.13 102.38 106.09 99.32 91.28 102.67 106.88
800 Hz 96.51 88.26 99.82 102.28 97.8 88.76 100.64 103.13
1000 Hz 97.1 88.55 100.34 101.92 98.88 89.34 101.58 102.28
1250 Hz 96.55 88.92 100.45 101.73 98.16 89.52 101.48 102.52
1600 Hz 97.25 89.76 101.19 102.12 99.13 90.42 102.32 103.16
2000 Hz 97.87 90.18 101.65 102.3 100.24 91.03 103.04 103.46
2500 Hz 96.52 88.28 99.84 100.3 98.37 89.06 101.15 101.47
3150 Hz 95.38 86.86 98.49 99.07 97.48 87.75 99.93 100.29
4000 Hz 92.69 83.77 95.52 96.26 95.29 84.96 97.33 97.63
5000 Hz 91.65 82.34 94.37 95.6 94.35 83.69 96.31 97.1
6300 Hz 90.21 80.66 92.95 94.91 92.87 82.04 94.83 96.24
8000 Hz 87.93 78.01 90.57 93.58 90.37 79.34 92.29 95.03
10000 Hz 86.05 76.13 88.9 93.45 87.27 76.79 89.76 94.65
Table 6.4-8 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 at Southwest corner, Press
box-1
The maximum, minimum and average total sound pressure levels (SPL) at 1000 Hz from EASE
simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were
grouped together to draw comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the
reconfigured speaker system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had
higher SPL values than the existing Coliseum due to the presence of the enlarged glass box in the press box which
reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed
to contain the sound and reflect it within the stadium which resulted in higher SPL values (Table 6.4-9).
289
Frequency
Maximum Minimum
Average
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 57.11 66.89 66.12 60 58.4 60.65 55.68 57.69 57.32 60.87 56.31 58.22
125 Hz 61.06 71.23 70.51 64.41 62.57 64.76 59.87 61.88 61.34 65 60.55 62.45
160 Hz 62.79 73.54 72.94 67.02 64.82 66.57 62.14 64.15 63.25 66.89 62.91 64.77
200 Hz 64.25 76.56 76.17 69.23 66.87 68.05 63.99 66.01 64.94 68.44 64.87 66.64
250 Hz 66.92 79.75 79.42 73.28 70.25 70.74 67.06 69.07 67.89 71.2 68.01 69.81
315 Hz 66.82 79.29 78.94 73.55 70.82 70.78 67.29 69.31 68.11 71.3 68.33 70.08
400 Hz 68.76 80.68 80.26 75.95 73.11 73.1 69.79 71.8 70.23 73.6 70.75 72.58
500 Hz 72.22 84.56 84.17 80.21 76.65 76.81 73.66 75.67 73.91 77.35 74.66 76.58
630 Hz 71.84 85.97 85.77 81.6 77.46 75.59 72.62 74.64 74.26 76.46 74.11 75.74
800 Hz 69.73 82.92 82.73 80.39 76.74 72.5 69.72 71.73 73.48 73.74 71.71 72.95
1000 Hz 70.09 82.18 81.96 79.25 77.6 72.62 70.02 72.03 74.85 73.91 72.04 73.3
1250 Hz 69.9 83.34 83.14 79.55 76.88 73.33 70.67 72.68 73.8 74.34 72.29 73.92
1600 Hz 70.88 84.98 84.8 81.86 77.93 74.22 71.48 73.49 74.88 75.28 73.2 74.78
2000 Hz 71.88 85.72 85.56 82.98 79.25 74.6 71.86 73.87 76.19 75.87 73.88 75.26
2500 Hz 70.27 84.8 84.68 82.1 78.34 72.59 69.88 71.89 74.42 73.93 71.99 73.35
3150 Hz 69.52 84.64 84.55 82.17 78.41 71.18 68.56 70.58 73.7 72.72 70.9 72.12
4000 Hz 66.98 82.09 82.01 79.51 75.89 68.07 65.6 67.61 71.75 69.77 68.08 69.2
5000 Hz 65.96 81.27 81.21 78.61 74.66 66.65 64.55 66.57 71.05 68.44 67 68.11
6300 Hz 64.42 80.22 80.17 77.54 73.51 65.13 63.42 65.44 69.69 66.78 65.56 66.83
8000 Hz 61.93 78.46 78.43 75.77 70.9 62.58 61.25 63.26 67.41 64.13 63.12 64.48
10000 Hz 59.64 77.7 77.68 73.94 67.64 60.95 59.93 61.95 63.4 62.04 61.19 62.84
Table 6.4-9 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 Maximum, Minimum &
Average
The maximum, minimum and average total sound pressure levels (SPL) at 1000 Hz from EASE
simulations of Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were
grouped together to draw comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the
reconfigured speaker system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had
higher SPL values than the existing Coliseum due to the presence of the enlarged glass box in the press box which
reflected the audience noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed
to contain the sound and reflect it within the stadium which resulted in higher SPL values (Table 6.4-10). Coliseum
redesign-2 setup-1 & setup-2 had the highest SPL values of 114.5 dB and 112.92 dB respectively.
290
Frequency
Maximum Minimum
Average
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 98.6 81.89 94.87 107.85 84.31 75.65 84.43 105.54 84.93 75.87 85.06 106.07
125 Hz 103.08 86.23 99.26 109.26 88.17 79.76 88.62 106.73 88.89 80 89.3 107.3
160 Hz 105.12 88.54 101.69 109.17 89.65 81.57 90.89 106.3 90.61 81.89 91.66 106.92
200 Hz 107.08 91.56 104.92 108.88 90.82 83.05 92.74 105.66 92.06 83.44 93.62 106.29
250 Hz 110.09 94.75 108.17 110.63 93.19 85.74 95.81 106.42 94.72 86.2 96.76 107.16
315 Hz 109.07 94.29 107.69 108.9 92.75 85.78 96.04 104.66 94.6 86.3 97.08 105.43
400 Hz 108.76 95.68 109.01 109.5 94.57 88.1 98.54 105.35 96.53 88.6 99.5 106.13
500 Hz 113.13 99.56 112.92 112.16 97.77 91.81 102.41 107.62 99.99 92.35 103.41 108.53
630 Hz 112.41 100.97 114.52 112.25 96.25 90.59 101.37 105.29 99.59 91.46 102.86 106.39
800 Hz 111.5 97.92 111.48 109.94 92.85 87.5 98.47 101.28 97.45 88.74 100.46 102.5
1000 Hz 110.92 97.18 110.71 108 92.64 87.62 98.77 100.78 97.76 88.91 100.79 102.05
1250 Hz 110.49 98.34 111.89 107.7 93.37 88.33 99.42 100.83 97.6 89.34 101.05 102.07
1600 Hz 112.71 99.98 113.55 109.61 94.31 89.22 100.23 101.24 98.6 90.28 101.95 102.53
2000 Hz 114.19 100.72 114.31 110.53 94.78 89.6 100.61 101.42 99.59 90.87 102.63 102.81
2500 Hz 113.39 99.8 113.43 109.55 93.32 87.59 98.63 99.34 97.97 88.93 100.74 100.8
3150 Hz 113.44 99.64 113.3 109.72 92.51 86.18 97.31 98.13 97.23 87.72 99.65 99.67
4000 Hz 110.97 97.09 110.76 107.26 90.06 83.07 94.35 95.36 94.69 84.77 96.83 96.95
5000 Hz 110.34 96.27 109.96 106.86 89.37 81.65 93.3 94.82 93.68 83.44 95.75 96.36
6300 Hz 109.19 95.22 108.92 106.39 88.61 80.13 92.17 94.29 92.17 81.78 94.31 95.68
8000 Hz 107.5 93.46 107.18 105.62 86.81 77.58 90 93.11 89.72 79.13 91.87 94.33
10000 Hz 105.48 92.7 106.43 105.19 85.62 75.95 88.68 93.2 87.47 77.04 89.94 94.09
Table 6.4-10 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 Maximum, Minimum &
Average
Scenario-1 mappings of total sound pressure level (SPL) EASE simulation mappings of Coliseum,
Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw
comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the reconfigured speaker
system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had higher SPL values than
the existing Coliseum due to the presence of the enlarged glass box in the press box which reflected the audience
noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed to contain the sound
and reflect it within the stadium which resulted in higher SPL values (Fig 6.4-2). It can also been seen in the total
SPL spread
291
Figure 6.4-2 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-1 mapping
Scenario-2 mappings of total sound pressure level (SPL) EASE simulation mappings of Coliseum,
Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw
comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the reconfigured speaker
system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had higher SPL values than
the existing Coliseum due to the presence of the enlarged glass box in the press box which reflected the audience
noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed to contain the sound
and reflect it within the stadium which resulted in higher SPL values (Fig 6.4-3). Coliseum redesign-2 setup-1 had
the existing speaker setup which calculated the highest SPL from the student section mapping area which is closer to
the USC band speaker systems. Coliseum redesign-2 setup-1 & setup-2 had the highest SPL values of 114.5 dB and
112.92 dB respectively. Mapping comparison shows that the Coliseum redesign-2 setup-2 has an consistent spread
of SPL values throughout the Coliseum which was the design intent.
292
Figure 6.4-3 Los Angeles Memorial Coliseum EASE simulation comparison of Total SPL scenario-2 mapping
6.4.2 C7
C7 mapping at 1000 Hz at the Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum
redesign setup-2 was simulated in EASE. C7 is ratio of direct and reverberant sound after 7 ms. It can be used to
analyze the strength of the direct sound field (ADA (Acoustic Design Anhert), 2009). Values above -15 dB are
considered good. Values closer to 0 dB are considered better (ADA (Acoustic Design Anhert), 2009).
C7 values help us understand the ratio between direct sound and reverberant sound. It is calculated at an
interval of 7 microseconds between the direct and reflected sound.
C7 values at student section-1, student section-2 at Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw a comparison. C7 simulation results show that
the all the values in Coliseum redesign-2 setup-2 with the reconfigred speaker system are in the acceptable range
(Table 6.4-11).
293
Frequency
Student section-1 Student section-2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -3.09 -9.51 -9.15 -13.26 -7.51 -14 -17.1 -13.09
125 Hz -2.23 -8.88 -8.57 -12.77 -6.61 -13.34 -16.86 -12.55
160 Hz -0.55 -7.49 -7.54 -12.14 -4.82 -11.86 -16.45 -11.79
200 Hz 0.96 -6.13 -6.63 -11.68 -3.26 -10.55 -15.99 -11.11
250 Hz 2.61 -4.53 -5.65 -10.4 -1.69 -9.22 -17.19 -10.02
315 Hz 4.08 -3.63 -4.9 -10.27 -0.22 -8.28 -16.01 -9.47
400 Hz 4.79 -3.47 -5 -10.35 0.41 -8.23 -15.92 -9.22
500 Hz 5.29 -3.39 -4.65 -8.92 1.33 -7.75 -17.59 -8.32
630 Hz 8.07 -0.37 -2 -7.13 4.03 -4.89 -19.66 -7
800 Hz 10.81 2.47 0.68 -6 7.06 -2 -23.36 -5.93
1000 Hz 11.85 2.93 1.67 -5.31 8.78 -0.82 -21.63 -5.41
1250 Hz 10.49 1.39 -0.27 -5.62 7 -2.86 -19.46 -5.15
1600 Hz 10.63 1.81 0.15 -5.24 7.16 -2.52 -21.8 -4.67
2000 Hz 11.42 3.28 1.39 -4.36 7.99 -1.25 -22.17 -3.84
2500 Hz 12.14 4.33 1.47 -3.82 7.79 -1.15 -24.14 -4.19
3150 Hz 13.06 6.05 2.22 -3.72 7.88 -0.31 -27.05 -3.72
4000 Hz 13.1 6.9 3.48 -2.74 8.57 1.08 -26.66 -3.06
5000 Hz 12.71 7.12 4.08 -2.25 8.73 2.03 -30.26 -2.43
6300 Hz 12.43 7.39 3.58 -2.65 8.23 1.9 -30.11 -3.02
8000 Hz 11.62 7.35 3.34 -2.96 7.74 2.01 -33.33 -3.35
10000 Hz 9.39 5.09 -0.18 -5.53 4.23 -1.2 -32.4 -3.7
Table 6.4-11 Los Angeles Memorial Coliseum EASE simulation comparison of C7 at student section- 1, student section- 2
C7 values at general public-1, general public-2 at Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw a comparison. Results comparison show that
Coliseum redesign-2 setup-1 has more of the values in the acceptable range for most of the frequency range. C7
simulation results show that the all the values in Coliseum redesign-2 setup-2 with the reconfigred speaker system
are in the acceptable range (Table 6.4-12).
294
Frequency
General Public- 1 General Public- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -17.9 -21.9 -8.8 -13.56 -9.53 -13.46 -11.82 -10.8
125 Hz -17.35 -21.57 -8.32 -13.02 -8.75 -12.87 -11.52 -10.31
160 Hz -16.22 -20.69 -7.69 -12.15 -7.43 -11.76 -11.29 -9.67
200 Hz -15.18 -19.83 -7.28 -11.35 -6.46 -10.97 -11.5 -9.25
250 Hz -15.83 -20.65 -6.27 -10.43 -4.95 -9.53 -11.31 -8.18
315 Hz -14.15 -19.26 -6.24 -9.66 -4.43 -9.31 -11.1 -8.18
400 Hz -13.49 -19.02 -6.62 -9.17 -4.29 -9.55 -11.7 -8.58
500 Hz -14.66 -20.54 -5.19 -8.66 -2.61 -7.86 -12.36 -7.04
630 Hz -16.98 -22.3 -2.82 -7.69 -0.33 -5.17 -10.14 -4.52
800 Hz -21.14 -25.7 -2.75 -6.76 -0.21 -4.92 -11.87 -4.4
1000 Hz -19.32 -23.82 -5.85 -6.37 -3.42 -7.76 -13.36 -7.42
1250 Hz -16.5 -21.81 -3.68 -5.59 -0.88 -5.74 -13.48 -5.34
1600 Hz -19.03 -24.2 -2.78 -5.03 0.05 -4.95 -14.77 -4.47
2000 Hz -19.99 -24.49 -3.4 -4.8 -0.96 -5.44 -14.04 -4.97
2500 Hz -22.27 -26.41 -3.16 -4.74 -0.69 -5.28 -15.91 -4.81
3150 Hz -25.68 -29.21 -3.37 -5.55 -1.24 -5.36 -16.83 -4.99
4000 Hz -25.58 -28.69 -3.77 -4.71 -1.97 -5.58 -17.1 -5.32
5000 Hz -29.18 -31.99 -3.79 -4.67 -2.05 -5.36 -17.38 -5.38
6300 Hz -28.58 -31.63 -2.47 -4.38 -0.67 -3.82 -18.09 -4.19
8000 Hz -31.57 -34.58 -1.45 -4.46 0.19 -2.53 -17.82 -3.2
10000 Hz -30.34 -33.41 0.45 -4.88 2.23 -0.44 -17.06 -1.38
Table 6.4-12 Los Angeles Memorial Coliseum EASE simulation comparison of C7 at general public- 1, general public- 2
C7 values at Titantron-1, Titantron-2 at Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-1,
Coliseum redesign setup-2 were grouped together to draw a comparison. Results comparison show that Coliseum
redesign-2 setup-1 has more of the values in the acceptable range for most of the frequency range. C7 simulation
results show that the all the values in Coliseum redesign-2 setup-2 with the reconfigred speaker system are in the
acceptable range (Table 6.4-13).
295
Frequency
Titantron- 1 Titantron- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -12.54 -16.43 -4.41 -13.77 -5.1 -8.91 -13.86 -6.29
125 Hz -11.94 -16.03 -4.01 -13.46 -4.41 -8.4 -13.41 -5.89
160 Hz -11.03 -15.33 -3.59 -13.22 -3.34 -7.53 -12.8 -5.46
200 Hz -10.68 -15.16 -3.58 -13.42 -2.77 -7.17 -12.49 -5.45
250 Hz -9.99 -14.56 -2.78 -13.17 -1.51 -5.94 -11.94 -4.58
315 Hz -9.31 -14.13 -2.94 -12.97 -1.19 -5.92 -11.61 -4.77
400 Hz -9.39 -14.6 -3.41 -13.57 -1.18 -6.26 -12.25 -5.26
500 Hz -9.57 -15.13 -1.8 -14.22 0.61 -4.35 -11.65 -3.51
630 Hz -7.66 -12.47 -0.29 -11.77 2.14 -2.57 -9.8 -1.88
800 Hz -9.62 -13.86 -2.35 -13.31 0.1 -4.41 -9.65 -3.84
1000 Hz -10.97 -15.2 -4.68 -14.78 -2.39 -6.46 -9.74 -6.04
1250 Hz -10.6 -15.55 -1.85 -15.07 0.9 -3.84 -10.87 -3.4
1600 Hz -12.02 -16.88 -2.39 -16.31 0.33 -4.46 -11.77 -3.93
2000 Hz -11.76 -15.95 -3.45 -15.44 -1.08 -5.37 -11.22 -4.86
2500 Hz -13.88 -17.75 -3.11 -17.27 -0.98 -4.99 -10.74 -4.49
3150 Hz -15.22 -18.44 -4.06 -18.04 -2.38 -5.71 -11.6 -5.31
4000 Hz -15.73 -18.55 -5.53 -18.27 -4.06 -7.04 -10.62 -6.74
5000 Hz -16.03 -18.64 -6.09 -18.6 -4.71 -7.36 -10.6 -7.31
6300 Hz -16.63 -19.24 -4.86 -19.49 -3.34 -6.03 -11.63 -6.28
8000 Hz -16.25 -18.85 -3.92 -19.42 -2.34 -4.94 -12.31 -5.51
10000 Hz -15.14 -18 -1.31 -18.93 0.56 -2.23 -15.14 -3.16
Table 6.4-13 Los Angeles Memorial Coliseum EASE simulation comparison of C7 at Titantron- 1, Titantron- 2
C7 values at southwest corner, press box-1 at Coliseum, Coliseum redesign-1, Coliseum redesign-2 setup-
1, Coliseum redesign setup-2 were grouped together to draw a comparison. Results comparison show that Coliseum
redesign-2 setup-1 has more of the values in the acceptable range for most of the frequency range. C7 simulation
results show that the all the values in Coliseum redesign-2 setup-2 with the reconfigred speaker system are in the
acceptable range (Table 6.4-14).
296
Frequency
Southwest corner Press box- 1
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -14.63 -8.91 -13.86 -6.29 -13.12 -16.68 -30.31 -15.9
125 Hz -13.87 -8.4 -13.41 -5.89 -12.19 -15.99 -30.12 -15.37
160 Hz -12.52 -7.53 -12.8 -5.46 -10.43 -14.51 -29.84 -14.6
200 Hz -11.58 -7.17 -12.49 -5.45 -8.89 -13.21 -29.1 -13.73
250 Hz -10.44 -5.94 -11.94 -4.58 -7.33 -11.98 -31.21 -12.42
315 Hz -9.56 -5.92 -11.61 -4.77 -5.91 -10.92 -31.1 -11.93
400 Hz -9.63 -6.26 -12.25 -5.26 -5.31 -10.78 -30.84 -11.4
500 Hz -8.45 -4.35 -11.65 -3.51 -4.36 -10.38 -32.09 -10.8
630 Hz -6.48 -2.57 -9.8 -1.88 -1.74 -8.2 -33.78 -9.23
800 Hz -6.4 -4.41 -9.65 -3.84 1.32 -5.24 -40.62 -8.13
1000 Hz -6.52 -6.46 -9.74 -6.04 3 -3.56 -38.43 -10.26
1250 Hz -7.07 -3.84 -10.87 -3.4 1.23 -5.4 -35.66 -8.73
1600 Hz -8.03 -4.46 -11.77 -3.93 1.35 -5.35 -37.18 -7.37
2000 Hz -7.59 -5.37 -11.22 -4.86 2.17 -4.5 -40.01 -6.88
2500 Hz -7.62 -4.99 -10.74 -4.49 1.79 -4.29 -42.36 -6.27
3150 Hz -8.78 -5.71 -11.6 -5.31 1.69 -3.98 -44.92 -5.76
4000 Hz -8.08 -7.04 -10.62 -6.74 2.2 -2.94 -46.6 -5.65
5000 Hz -8.2 -7.36 -10.6 -7.31 2 -2.47 -49.7 -5.5
6300 Hz -9.36 -6.03 -11.63 -6.28 1.13 -2.7 -52.23 -6.09
8000 Hz -10.23 -4.94 -12.31 -5.51 0.07 -3.05 -59.27 -6.32
10000 Hz -13.03 -2.23 -15.14 -3.16 -4.28 -6.74 -62.34 -7.63
Table 6.4-14 Los Angeles Memorial Coliseum EASE simulation comparison of C7 at Southwest corner, Press box-1
The maximum, minimum and average C7 values from EASE simulations of Coliseum, Coliseum redesign-
1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. Results
comparison show that Coliseum redesign-2 setup-1 has more of the values in the acceptable range for most of the
frequency range. C7 simulation results show that the all the values in Coliseum redesign-2 setup-2 with the
reconfigred speaker system are in the acceptable range (Table 6.4-15).
297
Frequency
Maximum Minimum
Average
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 12.3 4.79 -30.31 -2.98 -24.79 -35.91 -13.24 -200 -12.96 -18.08 -4.7 -16.2
125 Hz 12.85 5.07 -30.12 -2.47 -23.99 -35.74 -12.85 -200 -12.24 -17.59 -4.15 -15.73
160 Hz 13.26 5.68 -29.84 -1.61 -22.65 -35.15 -12.23 -200 -10.86 -16.49 -3.22 -15.16
200 Hz 13.74 7.47 -29.1 -0.8 -21.39 -33.92 -11.57 -200 -9.54 -15.42 -2.26 -14.75
250 Hz 14.43 8.05 -31.21 0.27 -22.78 -35.79 -11.51 -200 -8.77 -14.9 -1.01 -13.72
315 Hz 14.03 7.53 -31.1 0.66 -21.84 -37.53 -11.16 -200 -7.8 -14.35 -0.27 -13.46
400 Hz 11.95 6.48 -30.84 0.33 -22.84 -38.75 -11.4 -200 -7.45 -14.45 -0.25 -13.15
500 Hz 13.09 6.76 -32.09 1.09 -26.78 -39.9 -11.63 -200 -7.16 -14.46 -0.31 -12.18
630 Hz 15.6 9.81 -33.78 4.36 -31.6 -41.45 -10.76 -200 -6.04 -13.17 2.53 -11.69
800 Hz 16.95 9.89 -40.62 6.56 -32.74 -44.32 -11.17 -200 -6.09 -13.07 5.16 -11.71
1000 Hz 16.7 8.92 -38.43 4.79 -31.2 -41.36 -10.5 -200 -4.94 -12.29 5.43 -10.76
1250 Hz 16.21 9.42 -35.66 4.26 -27.69 -41.29 -10.57 -200 -4.86 -12.61 3.98 -10.14
1600 Hz 17.68 10.25 -37.18 5.94 -27.91 -41.63 -10.84 -200 -5.27 -12.88 4.47 -10.03
2000 Hz 17.69 10.61 -40.01 6.38 -31.61 -44.29 -10.8 -200 -5.42 -12.72 5.93 -9.79
2500 Hz 18.81 11.8 -42.36 7.48 -35.41 -46.42 -11.37 -200 -6.24 -13.17 6.95 -9.46
3150 Hz 19.41 13.14 -44.92 9.13 -38.32 -50.95 -11.91 -200 -7.14 -13.51 8.58 -9.23
4000 Hz 19.56 13.75 -46.6 9.23 -41 -51.67 -11.92 -200 -7.44 -13.32 9.3 -9.36
5000 Hz 19.82 14.41 -49.7 9.4 -43.89 -56.74 -13 -200 -8.57 -13.98 9.18 -9.83
6300 Hz 19.54 17.41 -52.23 9.94 -44.72 -57.19 -13.71 -200 -9.42 -14.39 9.08 -10.27
8000 Hz 19.71 23.28 -59.27 10.51 -50.2 -200 -15.81 -200 -11.6 -16.13 8.67 -11.12
10000 Hz 19.74 32.5 -62.34 10.78 -50.94 -200 -17.74 -200 -13.75 -18.08 6.11 -12.32
Table 6.4-15 Los Angeles Memorial Coliseum EASE simulation comparison of C7 Maximum, Minimum & Average
Mappings of C7 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. Results comparison show that
Coliseum redesign-2 setup-1 has more of the values in the acceptable range for most of the frequency range. C7
simulation results show that the aaverage C7 values in Coliseum redesign-2 setup-2 with the reconfigred speaker
system have all values in the accepable range (Fig 6.4-4). Average C7 values at the existing Coliseum are in the
acceptable range with a parts of the audience stands having unacceptable values.
298
Figure 6.4-4 Los Angeles Memorial Coliseum EASE simulation comparison of C7 mapping
6.4.3 C50
C50 measures the speech clarity which is the ratio between the early and late reflections in a space after 50
ms (ADA (Acoustic Design Anhert), 2009). Any value above 0 dB in a space are considered good (ADA (Acoustic
Design Anhert), 2009). Values above – 5 dB are considered good for spaces with higher reverberation (ADA
(Acoustic Design Anhert), 2009). EASE calculated the C50 values at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum C50 values with the C50 values for
each location.
C50 values at the student section-1, student section-2 from EASE simulations of Coliseum, Coliseum redesign-1,
Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw comparison (Table 6.4-16).
C50 values show that the existing Coliseum had a good speech clarity in the student sections due to their proximity
to the band speaker systems. The Coliseum redesign-2 setup-2 which had higher SPL values and better range of C7
values has a lower speech clarity values than the existing Coliseum. Possible reasons are the shifting the speaker
systems from the pitch level on the side of USC band to the partial roof system facing the audience. Since the study
focused on improving the total SPL levels in the stadium, further improvements to speech clarity have been left for
future work.
299
Frequency
Student section-1 Student section-2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -2.23 -8.55 -3.63 -9.48 -5.82 -11.8 -6.94 -9.09
125 Hz -1.38 -7.95 -3.1 -9.06 -4.99 -11.23 -6.44 -8.63
160 Hz 0.27 -6.65 -2.25 -8.56 -3.38 -10 -5.64 -8
200 Hz 1.75 -5.38 -1.37 -8.18 -1.96 -8.89 -4.91 -7.49
250 Hz 3.4 -3.88 -0.2 -7.32 -0.48 -7.75 -4.1 -6.67
315 Hz 4.89 -3 0.51 -7.13 0.94 -6.92 -3.43 -6.21
400 Hz 5.67 -2.8 0.58 -7.12 1.63 -6.76 -3.42 -6.09
500 Hz 6.26 -2.67 0.58 -6.08 2.57 -6.28 -3.08 -5.33
630 Hz 8.98 0.15 3.23 -4.63 5.09 -3.93 -0.89 -4
800 Hz 11.67 2.89 5.76 -3.81 7.97 -1.33 1.51 -3.28
1000 Hz 12.72 3.35 6.04 -3.3 9.67 -0.22 2.45 -2.93
1250 Hz 11.44 1.89 4.67 -3.59 8.01 -2.04 0.71 -2.8
1600 Hz 11.59 2.31 5.18 -3.23 8.19 -1.7 1.14 -2.5
2000 Hz 12.37 3.75 6.61 -2.57 8.98 -0.52 2.31 -1.97
2500 Hz 13.11 4.81 7.66 -2.01 8.82 -0.36 2.46 -2.01
3150 Hz 14.04 6.54 9.31 -1.79 8.93 0.49 3.22 -1.54
4000 Hz 14.15 7.46 10.11 -0.98 9.67 1.88 4.51 -1.12
5000 Hz 13.88 7.79 10.09 -0.41 9.94 2.92 5.19 -0.62
6300 Hz 13.77 8.23 10.16 -0.62 9.64 3.03 4.93 -0.93
8000 Hz 13.23 8.46 10.02 -0.52 9.44 3.49 5.02 -1.07
10000 Hz 11.5 6.78 8.01 -1.81 6.68 1.46 2.62 -0.99
Table 6.4-16 Los Angeles Memorial Coliseum EASE simulation comparison of C50 at student section- 1, student section- 2
C50 values at the general public-1, general public-2 from EASE simulations of Coliseum, Coliseum
redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw comparison
(Table 6.4-17). C50 values of the existing Coliseum are in the unaaceptable range due to their proximity to the band
speaker systems. Coliseum redesign-2 setup-2 had the speaker systems consistently spread throughout the stadium
which provided better C50 values than the existing conditions. Possible reasons are the shifting the speaker systems
from the pitch level on the side of USC band to the partial roof system facing the audience. Since the study focused
on improving the total SPL levels in the stadium, further improvements to speech clarity have been left for future
work.
300
Frequency
General Public- 1 General Public- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -14.12 -18.22 -13.43 -8.44 -6.39 -10.61 -5.76 -7.25
125 Hz -13.58 -17.89 -13.18 -8.01 -5.65 -10.08 -5.32 -6.83
160 Hz -12.54 -17.05 -12.81 -7.4 -4.46 -9.11 -4.82 -6.35
200 Hz -11.59 -16.27 -12.42 -6.85 -3.63 -8.45 -4.55 -6.08
250 Hz -12.02 -16.77 -13.33 -6.33 -2.12 -7.11 -3.59 -5.17
315 Hz -10.55 -15.6 -12.35 -5.72 -1.73 -6.96 -3.67 -5.24
400 Hz -9.97 -15.37 -12.28 -5.47 -1.43 -7 -3.86 -5.41
500 Hz -10.91 -16.43 -13.53 -5.13 0.79 -5.21 -2.19 -3.85
630 Hz -12.84 -17.51 -14.95 -4.24 2.41 -3.22 -0.51 -2.15
800 Hz -15.53 -18.92 -16.71 -3.82 0.99 -3.78 -1.48 -2.88
1000 Hz -14.49 -17.93 -15.84 -3.45 -1.62 -5.81 -3.79 -4.94
1250 Hz -12.37 -16.84 -14.56 -3.01 1.82 -3.61 -1.26 -2.75
1600 Hz -14.31 -18.16 -15.9 -2.73 2.07 -3.29 -0.88 -2.37
2000 Hz -14.97 -18.08 -15.92 -2.63 1.52 -3.35 -1.05 -2.43
2500 Hz -16.17 -18.62 -16.57 -2.25 1.13 -3.57 -1.28 -2.63
3150 Hz -17.32 -18.88 -17.01 -2.88 0.63 -3.53 -1.38 -2.66
4000 Hz -17.22 -18.41 -16.71 -2.21 0.04 -3.52 -1.57 -2.73
5000 Hz -17.29 -18.08 -16.68 -2.13 -0.32 -3.41 -1.78 -2.86
6300 Hz -15.7 -16.88 -15.68 -1.72 1.16 -1.87 -0.44 -1.7
8000 Hz -14.4 -15.63 -14.69 -1.53 2.41 -0.3 0.88 -0.44
10000 Hz -12.7 -14 -13.28 -1.3 5.35 2.33 3.43 1.86
Table 6.4-17 Los Angeles Memorial Coliseum EASE simulation comparison of C50 at general public- 1, general public- 2
C50 values at the Titantron-1, Titantron-2 from EASE simulations of Coliseum, Coliseum redesign-1,
Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw comparison (Table 6.4-18).
C50 values of the existing Coliseum are in the unaaceptable range due to their proximity to the band speaker
systems. Coliseum redesign-2 setup-2 had the speaker systems consistently spread throughout the stadium which
provided better C50 values than the existing conditions. Possible reasons are the shifting the speaker systems from
the pitch level on the side of USC band to the partial roof system facing the audience. Since the study focused on
improving the total SPL levels in the stadium, further improvements to speech clarity have been left for future work.
301
Frequency
Titantron- 1 Titantron- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -7.93 -12.1 -7.25 -8.92 -3.02 -7.19 -2.31 -4.1
125 Hz -7.3 -11.69 -6.93 -8.6 -2.3 -6.7 -1.9 -3.69
160 Hz -6.38 -11 -6.71 -8.37 -1.24 -5.88 -1.57 -3.35
200 Hz -6.02 -10.8 -6.93 -8.52 -0.8 -5.64 -1.73 -3.47
250 Hz -5.28 -10.18 -6.72 -8.27 0.64 -4.37 -0.85 -2.59
315 Hz -4.64 -9.8 -6.57 -8.12 0.85 -4.41 -1.13 -2.85
400 Hz -4.6 -10.07 -7 -8.47 1.06 -4.59 -1.45 -3.14
500 Hz -4.54 -10.25 -7.35 -8.73 3.57 -2.5 0.51 -1.25
630 Hz -2.9 -8.15 -5.6 -7.01 4.17 -1.29 1.32 -0.28
800 Hz -5.62 -9.74 -7.68 -8.67 0.89 -3.59 -1.44 -2.68
1000 Hz -7.25 -10.98 -9.13 -9.89 -0.39 -4.58 -2.66 -3.76
1250 Hz -6.13 -10.67 -8.56 -9.48 2.78 -2.43 -0.2 -1.63
1600 Hz -7.45 -11.57 -9.49 -10.16 1.92 -3.11 -0.86 -2.2
2000 Hz -7.6 -11.1 -9.23 -9.85 0.2 -4.04 -2.01 -3.12
2500 Hz -9.12 -12 -10.26 -10.62 0.19 -3.73 -1.76 -2.83
3150 Hz -10.4 -12.44 -11 -11.07 -0.75 -3.99 -2.25 -3.17
4000 Hz -10.66 -12.27 -11.03 -10.98 -2.67 -5.28 -3.77 -4.44
5000 Hz -10.47 -11.83 -10.78 -10.68 -3.07 -5.28 -4.04 -4.63
6300 Hz -9.88 -11.11 -10.2 -10.06 -1.52 -3.84 -2.67 -3.45
8000 Hz -8.41 -9.67 -8.87 -8.83 -0.14 -2.43 -1.39 -2.3
10000 Hz -6.2 -7.7 -6.96 -7.12 3.26 0.49 1.52 0.2
Table 6.4-18 Los Angeles Memorial Coliseum EASE simulation comparison of C50 at Titantron- 1, Titantron- 2
C50 values at the southwest corner, press box-1 from EASE simulations of Coliseum, Coliseum redesign-1,
Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw comparison (Table 6.4-19).
C50 values of the existing Coliseum are in the unaaceptable range due to their proximity to the band speaker
systems. Coliseum redesign-2 setup-2 had the speaker systems consistently spread throughout the stadium which
provided better C50 values than the existing conditions. Southwest corner had lower C 50 values despite placing a a
set of speakes fafcing the stands in the corner section of the stadium. Press box-1 had several acceptable C50 values
in the higher frequency range in the existing conditions. Coliseum redesign-2 setup-2 had values which are slightly
less than the acceptable values range without much fluctutation in the values compared to the other simulation
setups. Since the study focused on improving the total SPL levels in the stadium, further improvements to speech
clarity have been left for future work.
302
Frequency
Southwest corner Press box- 1
Existing Coliseum (dB)
Coliseum redesign-1
(dB)
Coliseum redesign-2
setup-1 (dB)
Coliseum redesign-2
setup-2 (dB)
Existing Coliseum (dB)
Coliseum redesign-1
(dB)
Coliseum redesign-2
setup-1 (dB)
Coliseum redesign-2
setup-2 (dB)
100 Hz -9.94 -14.23 -9.51 -14.02 -9.21 -13.28 -8.41 -9.83
125 Hz -9.32 -13.78 -9.15 -13.63 -8.49 -12.74 -7.94 -9.34
160 Hz -8.32 -12.92 -8.75 -13.13 -7.2 -11.62 -7.25 -8.62
200 Hz -7.56 -12.26 -8.48 -12.84 -6.04 -10.62 -6.61 -7.96
250 Hz -6.76 -11.55 -8.14 -12.4 -4.81 -9.64 -5.96 -7.04
315 Hz -6.11 -11.07 -7.88 -12.13 -3.65 -8.8 -5.27 -6.51
400 Hz -5.89 -11.02 -8 -12.55 -3.03 -8.54 -5.16 -6.25
500 Hz -5.08 -10.48 -7.59 -12.05 -2.16 -8.13 -4.89 -5.67
630 Hz -4.09 -9.42 -6.75 -10.56 -0.1 -6.56 -3.52 -4.05
800 Hz -4.34 -9.15 -6.8 -10.34 2.52 -4.19 -1.3 -3.35
1000 Hz -4.65 -9.02 -6.92 -10.34 4.08 -2.7 0.04 -4.65
1250 Hz -4.5 -9.46 -7.15 -11.31 2.55 -4.21 -1.35 -3.58
1600 Hz -4.99 -9.73 -7.39 -11.89 2.71 -4.13 -1.2 -2.73
2000 Hz -4.72 -9.36 -7.03 -11.37 3.43 -3.37 -0.48 -2.49
2500 Hz -4.79 -8.94 -6.72 -10.91 3.15 -3.1 -0.17 -2.25
3150 Hz -5.29 -8.92 -6.83 -11.35 3.09 -2.73 0.1 -2.03
4000 Hz -4.62 -8.06 -6.07 -10.48 3.63 -1.69 0.97 -1.71
5000 Hz -4.32 -7.36 -5.66 -10.24 3.57 -1.07 1.23 -1.5
6300 Hz -4.12 -6.7 -5.3 -10.55 3.07 -0.91 1.04 -2.04
8000 Hz -3.52 -5.61 -4.51 -10.29 2.56 -0.64 0.88 -1.84
10000 Hz -2.62 -4.31 -3.47 -10.27 0.37 -1.88 -0.75 -2.7
Table 6.4-19 Los Angeles Memorial Coliseum EASE simulation comparison of C50 at Southwest corner, Press box-1
The maximum, minimum and average C50 values at 1000 Hz from EASE simulations of Coliseum,
Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw
comparison. Results comparison show that the maximum C50 values are in the acceptable range. The average C50
values for the existing Coliseum are better as part of the stands had the speaker systems were in closer to the
audience stands (Table 6.4-20). Since the study focused on improving the total SPL levels in the stadium, further
improvements to speech clarity have been left for future work.
303
Frequency
Maximum Minimum
Average
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 12.56 4.92 9.63 -2 -21.54 -35.86 -29.62 -18.57 -9.31 -13.99 -9.3 -10.55
125 Hz 13.13 5.22 9.85 -1.56 -21.08 -35.66 -29.43 -18.01 -8.65 -13.55 -8.94 -10.14
160 Hz 13.58 5.84 10.04 -0.77 -20 -35.09 -29.16 -17.5 -7.44 -12.61 -8.45 -9.68
200 Hz 14.08 7.64 11.4 0.14 -18.7 -33.92 -28.42 -17.28 -6.31 -11.72 -7.93 -9.41
250 Hz 14.82 8.25 11.69 1.72 -20.03 -35.79 -30.52 -17.17 -5.57 -11.21 -7.83 -8.69
315 Hz 14.51 7.75 11.08 1.91 -18.9 -37.33 -30.38 -16.69 -4.64 -10.66 -7.47 -8.44
400 Hz 12.51 6.74 9.99 1.84 -20.04 -37.77 -30.11 -16.83 -4.19 -10.58 -7.54 -8.21
500 Hz 13.69 7.04 10.22 2.02 -23.34 -37.29 -31.37 -17.2 -3.72 -10.38 -7.53 -7.41
630 Hz 16.34 10.08 13.11 5.3 -25.35 -38.2 -33.05 -17.3 -2.69 -9.34 -6.76 -6.96
800 Hz 17.69 10.19 13.08 8.03 -29.02 -43.72 -39.88 -21.66 -2.26 -8.78 -6.54 -7.11
1000 Hz 17.52 9.24 11.94 6.41 -27.21 -40.92 -37.69 -18.57 -1.43 -8.3 -6.2 -6.39
1250 Hz 17.05 9.75 12.51 5.6 -23.95 -39.97 -34.94 -18.32 -1.59 -8.7 -6.45 -6.02
1600 Hz 18.51 10.59 13.44 7.57 -24.81 -41.63 -36.4 -20.31 -1.9 -8.76 -6.49 -5.92
2000 Hz 18.52 10.96 13.79 8.4 -28.22 -43.34 -39.2 -21.45 -1.77 -8.34 -6.14 -5.79
2500 Hz 19.67 12.18 15.01 9.83 -31.86 -46.42 -41.52 -23.91 -2.12 -8.26 -6.13 -5.57
3150 Hz 20.29 13.56 16.35 11.49 -35.59 -50.13 -44.05 -26.48 -2.36 -7.92 -5.94 -5.29
4000 Hz 20.53 14.24 16.91 11.96 -37.41 -50.67 -45.61 -26.85 -2.34 -7.4 -5.58 -5.25
5000 Hz 20.89 15 17.32 12.28 -40.81 -55.65 -48.6 -30.71 -2.51 -7.01 -5.57 -5.37
6300 Hz 20.77 18.72 17.63 12.53 -40.61 -56.29 -50.92 -29.33 -2.7 -6.64 -5.55 -5.42
8000 Hz 21.17 24.99 18.33 13.18 -46.13 -63.07 -57.66 -32.83 -3.08 -6.27 -5.61 -5.48
10000 Hz 21.61 34.88 21.46 12.98 -47.98 -200 -60.23 -30.65 -3.61 -6.03 -5.72 -5.6
Table 6.4-20 Los Angeles Memorial Coliseum EASE simulation comparison of C50 Maximum, Minimum & Average
Mappings of C50 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. Results comparison show that
Coliseum redesign-2 setup-1 has more of the values in the acceptable range for most of the frequency range.
Existing Coliseum conditions have several parts of the stadium which have acceptable speech clarity measurements
while the Coliseum redesign-2 setup-2 which had an even spread of speaker systems had C50 values which are
below the acceptable range (Fig 6.4-5). This acoustical deficiency can be fixed by placing the speaker systems even
closer to the audience however the study focused on improving the total SPL levels in the stadium, further
improvements to speech clarity have been left for future work.
304
Figure 6.4-5 Los Angeles Memorial Coliseum EASE simulation comparison of C50 mapping
6.4.4 C80
C80 is ratio of direct and late reflections after 80ms (ADA (Acoustic Design Anhert), 2009). It is used for
evaluating the musical clarity of a space. EASE calculated the C80 values at 7 locations namely Student section-1,
Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results
from the simulation are exported as a table with the overall peak, average and minimum C80 values with the C80
values for each location.
C80 values at the student section-1, student section-2 from EASE simulations of Coliseum, Coliseum
redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw comparison
(Table 6.4-21). C80 values are calcualted for musical clarity in performance arenas, concert halls to finetune
acoustics for the listener to experience music with highest clarity. Acceptable range of C80 values are from 0-8 dB.
The stands within 30 feet radius of speakers (student sections and away fans closer to pitch) have values higher than
8 dB and the stands father than 200-250 feet have values lower than 0. The existing Coliseum had several parts of
the stands within acceptable values. It is difficult to maintain C80 values for a large arena within the acceptable
range. Since the study focused on improving the total SPL levels in the stadium, further improvements to musical
clarity have been left for future work.
305
Frequency
Student section-1 Student section-2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -1.35 -7.57 -2.53 -6.51 -4.33 -10.04 -5.09 -6.28
125 Hz -0.5 -7 -2.01 -6.12 -3.53 -9.51 -4.63 -5.86
160 Hz 1.14 -5.77 -1.22 -5.68 -2.02 -8.41 -3.95 -5.34
200 Hz 2.61 -4.57 -0.4 -5.32 -0.68 -7.41 -3.32 -4.89
250 Hz 4.25 -3.16 0.69 -4.69 0.75 -6.39 -2.62 -4.27
315 Hz 5.77 -2.3 1.4 -4.45 2.14 -5.63 -2.01 -3.84
400 Hz 6.64 -2.05 1.52 -4.37 2.9 -5.39 -1.91 -3.68
500 Hz 7.31 -1.87 1.58 -3.58 3.88 -4.9 -1.56 -3.08
630 Hz 9.99 0.75 4.05 -2.43 6.24 -2.92 0.29 -1.99
800 Hz 12.62 3.38 6.47 -1.87 8.98 -0.59 2.44 -1.46
1000 Hz 13.68 3.85 6.76 -1.48 10.66 0.47 3.33 -1.13
1250 Hz 12.49 2.47 5.48 -1.63 9.14 -1.15 1.8 -1.02
1600 Hz 12.67 2.9 6.02 -1.31 9.33 -0.81 2.24 -0.74
2000 Hz 13.42 4.31 7.43 -0.72 10.07 0.29 3.35 -0.23
2500 Hz 14.2 5.39 8.52 -0.16 9.98 0.51 3.56 -0.12
3150 Hz 15.14 7.14 10.2 0.12 10.1 1.38 4.35 0.34
4000 Hz 15.33 8.13 11.09 0.96 10.91 2.79 5.68 0.87
5000 Hz 15.2 8.59 11.2 1.61 11.31 3.92 6.46 1.44
6300 Hz 15.31 9.23 11.47 1.72 11.25 4.29 6.45 1.49
8000 Hz 15.08 9.79 11.64 2.24 11.38 5.12 6.89 1.85
10000 Hz 13.88 8.72 10.21 2.07 9.3 4.01 5.36 2.62
Table 6.4-21 Los Angeles Memorial Coliseum EASE simulation comparison of C80 at student section- 1, student section- 2
C80 values at the general public-1, general public-2 from EASE simulations of Coliseum, Coliseum
redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw comparison
(Table 6.4-22). C80 values are calcualted for musical clarity in performance arenas, concert halls to finetune
acoustics for the listener to experience music with highest clarity. Acceptable range of C80 values are from 0-8 dB.
The stands within 30 feet radius of speakers (student sections and away fans closer to pitch) have values higher than
8 dB and the stands father than 200-250 feet have values lower than 0. The existing Coliseum had several parts of
the stands within acceptable values. The Coliseum redesign-2 setup-2 with the reconfigured speaker system
improved the C80 from the existing conditions but still the values were below the acceptable range. It is difficult to
maintain C80 values for a large arena within the acceptable range. Since the study focused on improving the total
SPL levels in the stadium, further improvements to musical clarity have been left for future work.
306
Frequency
General Public- 1 General Public- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -8.99 -13.32 -8.58 -6.14 -4.79 -9.19 -4.25 -5.37
125 Hz -8.45 -12.94 -8.29 -5.74 -4.08 -8.69 -3.82 -4.97
160 Hz -7.58 -12.17 -7.99 -5.23 -2.95 -7.76 -3.37 -4.55
200 Hz -6.85 -11.49 -7.69 -4.75 -2.13 -7.1 -3.1 -4.28
250 Hz -6.71 -11.28 -7.89 -4.31 -0.79 -5.92 -2.28 -3.54
315 Hz -5.92 -10.61 -7.41 -3.8 -0.38 -5.7 -2.3 -3.54
400 Hz -5.37 -10.25 -7.19 -3.52 -0.01 -5.62 -2.38 -3.58
500 Hz -5.57 -10.29 -7.43 -3.19 1.98 -4.09 -0.95 -2.31
630 Hz -6.89 -10.48 -7.97 -2.53 3.27 -2.38 0.45 -0.94
800 Hz -8.54 -10.7 -8.54 -2.2 1.72 -2.88 -0.51 -1.62
1000 Hz -8.45 -10.32 -8.28 -1.86 -0.8 -4.57 -2.53 -3.3
1250 Hz -6.91 -9.81 -7.58 -1.41 2.64 -2.61 -0.17 -1.37
1600 Hz -7.52 -9.93 -7.72 -1.12 2.89 -2.3 0.21 -1
2000 Hz -8.23 -9.8 -7.7 -0.97 2.29 -2.33 0.05 -1.03
2500 Hz -8.32 -9.57 -7.56 -0.56 2.02 -2.43 -0.05 -1.08
3150 Hz -8.53 -9.21 -7.37 -0.91 1.58 -2.3 -0.09 -1.03
4000 Hz -8.18 -8.59 -6.92 -0.2 1.07 -2.16 -0.18 -0.97
5000 Hz -7.5 -7.79 -6.39 0.05 0.87 -1.86 -0.22 -0.9
6300 Hz -5.53 -6.42 -5.16 0.72 2.55 -0.23 1.24 0.35
8000 Hz -3.64 -4.83 -3.78 1.37 4.04 1.52 2.75 1.79
10000 Hz -1.39 -2.89 -2.03 2.34 7.72 4.59 5.84 4.54
Table 6.4-22 Los Angeles Memorial Coliseum EASE simulation comparison of C80 at general public- 1, general public- 2
C80 values at the titantron-1, titantron-2 from EASE simulations of Coliseum, Coliseum redesign-1,
Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw comparison (Table 6.4-23).
C80 values are calcualted for musical clarity in performance arenas, concert halls to finetune acoustics for the
listener to experience music with highest clarity. Acceptable range of C80 values are from 0-8 dB.
The stands within 30 feet radius of speakers (student sections and away fans closer to pitch) have values higher than
8 dB and the stands father than 200-250 feet have values lower than 0. The existing Coliseum had several parts of
the stands within acceptable values. The Coliseum redesign-2 setup-2 with the reconfigured speaker system
improved the C80 from the existing conditions but still the values were below the acceptable range. It is difficult to
maintain C80 values for a large arena within the acceptable range. Since the study focused on improving the total
SPL levels in the stadium, further improvements to musical clarity have been left for future work.
307
Frequency
Titantron- 1 Titantron- 2
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz -5.86 -10.24 -5.32 -6.44 -2.05 -6.43 -1.4 -2.94
125 Hz -5.25 -9.83 -4.99 -6.12 -1.33 -5.94 -0.99 -2.53
160 Hz -4.33 -9.11 -4.76 -5.87 -0.26 -5.12 -0.65 -2.19
200 Hz -3.87 -8.76 -4.83 -5.86 0.24 -4.81 -0.75 -2.23
250 Hz -3.22 -8.16 -4.65 -5.64 1.6 -3.61 0.06 -1.46
315 Hz -2.63 -7.76 -4.47 -5.47 1.86 -3.58 -0.16 -1.63
400 Hz -2.45 -7.77 -4.66 -5.54 2.14 -3.66 -0.38 -1.81
500 Hz -2.29 -7.72 -4.78 -5.55 4.51 -1.75 1.42 -0.13
630 Hz -1.43 -6.36 -3.76 -4.63 4.88 -0.65 2.09 0.68
800 Hz -4.07 -7.51 -5.48 -5.84 1.54 -2.76 -0.55 -1.51
1000 Hz -5.4 -8.19 -6.39 -6.49 0.28 -3.6 -1.64 -2.41
1250 Hz -4.11 -7.76 -5.68 -5.95 3.46 -1.61 0.71 -0.47
1600 Hz -5.05 -8.17 -6.14 -6.17 2.65 -2.19 0.15 -0.9
2000 Hz -5.54 -7.99 -6.2 -6.16 0.89 -3.01 -0.94 -1.72
2500 Hz -6.48 -8.29 -6.68 -6.4 0.92 -2.68 -0.68 -1.4
3150 Hz -7.43 -8.45 -7.16 -6.63 0 -2.86 -1.13 -1.68
4000 Hz -7.46 -8.11 -7.05 -6.42 -1.7 -3.8 -2.37 -2.59
5000 Hz -6.9 -7.41 -6.53 -5.88 -1.91 -3.6 -2.44 -2.55
6300 Hz -5.62 -6.19 -5.39 -4.81 -0.13 -2.01 -0.89 -1.19
8000 Hz -3.57 -4.36 -3.61 -3.19 1.64 -0.29 0.74 0.3
10000 Hz -0.45 -1.8 -1 -0.91 5.74 3.02 4.15 3.21
Table 6.4-23 Los Angeles Memorial Coliseum EASE simulation comparison of C80 at Titantron- 1, Titantron- 2
C80 values at the southwest corner, press box-1 from EASE simulations of Coliseum, Coliseum redesign-1,
Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw comparison (Table 6.4-24).
C80 values are calcualted for musical clarity in performance arenas, concert halls to finetune acoustics for the
listener to experience music with highest clarity. Acceptable range of C80 values are from 0-8 dB.
The stands within 30 feet radius of speakers (student sections and away fans closer to pitch) have values higher than
8 dB and the stands father than 200-250 feet have values lower than 0. The existing Coliseum had several parts of
the stands within acceptable values. The Coliseum redesign-2 setup-2 with the reconfigured speaker system
improved the C80 from the existing conditions but still the values were below the acceptable range. It is difficult to
maintain C80 values for a large arena within the acceptable range. Since the study focused on improving the total
SPL levels in the stadium, further improvements to musical clarity have been left for future work.
308
Frequency
Southwest corner Press box- 1
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-
1 (dB)
Coliseum redesign-2 setup-
2 (dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-
1 (dB)
Coliseum redesign-2 setup-
2 (dB)
100 Hz -7.12 -11.55 -6.78 -8.58 -6.69 -10.99 -6.08 -6.69
125 Hz -6.53 -11.12 -6.43 -8.23 -6.02 -10.5 -5.65 -6.26
160 Hz -5.6 -10.31 -6.09 -7.85 -4.86 -9.51 -5.09 -5.7
200 Hz -4.87 -9.66 -5.82 -7.51 -3.84 -8.62 -4.57 -5.16
250 Hz -4.17 -9.01 -5.54 -7.17 -2.72 -7.76 -4.01 -4.49
315 Hz -3.61 -8.55 -5.3 -6.84 -1.69 -7.02 -3.42 -4.01
400 Hz -3.27 -8.33 -5.25 -6.62 -1.03 -6.7 -3.24 -3.76
500 Hz -2.59 -7.84 -4.88 -6.27 -0.18 -6.27 -2.95 -3.3
630 Hz -2.09 -7.14 -4.42 -6.01 1.54 -5.05 -1.9 -2.05
800 Hz -2.59 -6.95 -4.57 -5.87 3.82 -3.09 -0.07 -1.53
1000 Hz -3.07 -6.83 -4.73 -5.82 5.25 -1.77 1.13 -2.41
1250 Hz -2.47 -6.91 -4.57 -5.6 3.97 -3.01 -0.01 -1.6
1600 Hz -2.75 -6.98 -4.6 -5.44 4.16 -2.89 0.19 -0.92
2000 Hz -2.55 -6.65 -4.29 -5.24 4.8 -2.2 0.86 -0.64
2500 Hz -2.66 -6.27 -4.03 -4.95 4.62 -1.88 1.22 -0.3
3150 Hz -2.87 -6.03 -3.93 -4.86 4.6 -1.44 1.56 -0.05
4000 Hz -2.18 -5.19 -3.18 -4.28 5.18 -0.39 2.47 0.39
5000 Hz -1.66 -4.36 -2.64 -4.06 5.28 0.36 2.85 0.72
6300 Hz -0.97 -3.35 -1.9 -3.54 5.11 0.86 2.99 0.65
8000 Hz 0.1 -1.92 -0.74 -2.71 5.07 1.61 3.29 1.29
10000 Hz 1.82 -0.05 0.94 -1.34 4 1.51 2.76 1.52
Table 6.4-24 Los Angeles Memorial Coliseum EASE simulation comparison of C80 at Southwest corner, Press box-1
The maximum, minimum and average C80 values at 1000 Hz from EASE simulations of Coliseum,
Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw
comparison. C80 values are calcualted for musical clarity in performance arenas, concert halls to finetune acoustics
for the listener to experience music with highest clarity. Acceptable range of C80 values are from 0-8 dB.
The stands within 30 feet radius of speakers (student sections and away fans closer to pitch) have values higher than
8 dB and the stands father than 200-250 feet have values lower than 0. The existing Coliseum had several parts of
the stands within acceptable values. The Coliseum redesign-2 setup-2 with the reconfigured speaker system
improved the C80 from the existing conditions but still the values were below the acceptable range. It is difficult to
maintain C80 values for a large arena within the acceptable range. Since the study focused on improving the total
SPL levels in the stadium, further improvements to musical clarity have been left for future work (Table 6.4-25).
309
Frequency
Maximum Minimum
Average
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
Existing Coliseum (dB)
Coliseum redesign-1 (dB)
Coliseum redesign-2 setup-1
(dB)
Coliseum redesign-2 setup-2
(dB)
100 Hz 12.86 5.09 9.99 -1.13 -19.74 -30.21 -23.05 -13.07 -6.41 -11.12 -6.37 -6.93
125 Hz 13.47 5.4 10.23 -0.72 -19.17 -29.68 -22.75 -12.56 -5.74 -10.68 -6 -6.55
160 Hz 13.97 6.05 10.44 0.04 -18 -28.42 -22.21 -11.85 -4.58 -9.78 -5.55 -6.15
200 Hz 14.49 7.86 11.81 0.93 -16.84 -27.14 -21.66 -11.22 -3.53 -8.96 -5.09 -5.84
250 Hz 15.29 8.49 12.13 2.41 -17.41 -26.43 -22.89 -10.1 -2.66 -8.32 -4.83 -5.34
315 Hz 15.07 8.02 11.56 2.64 -15.91 -25.76 -22.22 -10.01 -1.74 -7.77 -4.46 -5.04
400 Hz 13.16 7.05 10.52 2.61 -15.25 -25.81 -22.26 -10.28 -1.22 -7.56 -4.43 -4.8
500 Hz 14.41 7.39 10.8 2.77 -16.1 -25.82 -23.57 -9.18 -0.64 -7.22 -4.26 -4.25
630 Hz 17.8 10.42 13.68 5.9 -16.63 -24.88 -24.85 -8.68 0.46 -6.18 -3.43 -3.81
800 Hz 19.08 10.55 13.68 8.66 -17.42 -22.89 -26.47 -10.13 1.3 -5.3 -2.78 -3.68
1000 Hz 18.44 9.63 12.56 7.1 -16.46 -21.36 -25.24 -10.73 1.94 -4.95 -2.59 -3.32
1250 Hz 18.2 10.15 13.15 6.29 -17 -23.19 -25.31 -8.9 1.62 -5.4 -2.94 -3.08
1600 Hz 19.49 11 14.1 8.26 -17.35 -23.66 -27.29 -9.42 1.54 -5.26 -2.76 -2.86
2000 Hz 19.48 11.39 14.48 9.1 -18.26 -22.93 -27.03 -10.07 1.81 -4.73 -2.26 -2.61
2500 Hz 20.67 12.64 15.77 10.58 -18.7 -23.32 -27.99 -10.11 1.74 -4.41 -1.99 -2.27
3150 Hz 21.32 14.07 17.16 12.31 -19.05 -23.43 -28.83 -11.4 1.83 -3.8 -1.49 -1.88
4000 Hz 21.66 14.83 17.83 12.87 -20.07 -23.64 -31.07 -11.72 2.01 -3.11 -0.96 -1.48
5000 Hz 22.18 15.71 18.36 13.31 -21.13 -24.8 -33.72 -11.92 2.21 -2.39 -0.59 -1.22
6300 Hz 22.26 19.62 18.85 13.74 -22.5 -26.61 -35.85 -11.29 2.31 -1.71 -0.28 -0.81
8000 Hz 22.95 26.18 19.84 14.67 -24.99 -29.95 -41.12 -10.22 2.53 -0.75 0.28 -0.21
10000 Hz 23.87 36.54 23.43 14.9 -32.19 -38.64 -44.82 -11.73 2.49 0.01 0.61 0.54
Table 6.4-25 Los Angeles Memorial Coliseum EASE simulation comparison of C80 Maximum, Minimum & Average
Mappings of C80 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison (Fig 6.4-6). The Coliseum redesign
setup-2 with the reconfigured speaker systems had a evenly spread out mapping with several parts of the stadium
with acceptable C80 values without much range of values compared to the existing Coliseum but still the values
were below the acceptable range. It is difficult to maintain C80 values for a large arena within the acceptable range.
Since the study focused on improving the total SPL levels in the stadium, further improvements to musical clarity
have been left for future work.
310
Figure 6.4-6 Los Angeles Memorial Coliseum EASE simulation comparison of C80 mapping
6.4.5 First Arrival
First arrival timing mapping calculates the arrival time for any location from the nearest sound source.
EASE calculated the first arrival timings at 7 locations namely Student section-1, Student section-2, General
audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the simulation are
exported as a table with the overall peak, average and minimum first arrival timings with the first arrival timings for
each location (Table 6.4-26) (Fig 6.4-7).
For 20 feet, recommended maximum arrival time is 17.9 microseconds (GB Audio, 2018). Presence of
loudspeakers on both the ends of the stadium posed a challenge of the sound reaching the farther stands. EASE
simulation mapping shows the sound takes longer to reach the stands higher up the stadium which explain the lower
SPL values. Student sections are in the closer proximity to the speaker systems which had the highest SPL values
recorded in the field study and the EASE simulation results. Coliseum redesign-2 setup-2 which had a reconfigured
speaker system had average first arrival times reduced by 50 microseconds throughout the stadium. Longer arrival
times mean the farther the seats from the speaker system which equates to reduced SPL values. Decreasing the first
arrival timings by spreading out speaker systems made the total SPL values higher in the stadium.
311
Existing Coliseum Coliseum redesign-1 Coliseum redesign-2 setup-1 Coliseum redesign-2 setup-2
Maximum 409.3 600.84 428.31 228.92
Minimum 0 0 0 0
Average 200.79 205.05 201.57 152.19
Student section-1 93.36 91.59 91.59 135.95
Student section-2 159.63 158.56 158.56 135
General Public-1 182.87 182.87 182.87 140.17
General Public-2 57.26 57.25 57.25 57.25
Titantron-1 73.98 73.98 73.98 73.98
Titantron-2 31.23 31.23 31.23 31.23
Southwest corner 126.7 126.7 126.7 126.7
Press Box-1 227.66 215.03 211.99 128.98
Table 6.4-26 Los Angeles Memorial Coliseum EASE simulation comparison of first arrival timings at listeners seats
Figure 6.4-7 Los Angeles Memorial Coliseum EASE simulation comparison of first arrival timings
6.4.6 Articulation loss of consonants
Articulation loss of consonants is a percentage value that indicates the loss of speech intelligibility. Lower
numbers indicate higher speech intelligibility. 0-3% is excellent, 3-7% is good, 7-15% is fair, 15-33% is poor, above
33% is considered unacceptable. EASE calculated the AL cons at 7 locations namely Student section-1, Student
section-2, General audience-1, General audience-2, titantron, North-west corner, Away fans. The results from the
simulation are exported as a table with the overall peak, average and minimum AL cons percentages with the AL cons
percentages for each location (Table 6.4-27) (Fig 6.4-8).
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Acoustic design standards had the maximum acceptable % AL cons to be 15% which has been reduced to
10% in recent years. The acceptable range for spaces like lecture halls where speech intelligibility is critical is 5%.
Similar to the other parameters, AL cons values are higher than acceptable range in the stands located farther from the
speaker systems. Existing Coliseum conditions had acceptable AL cons % values and the Coliseum redesign-2 setup-2
had acceptable AL cons %values in all audience stands except for Titantron-1 and southwest corner. This acoustical
deficiency can be fixed by placing the speaker systems even closer to the audience however the study focused on
improving the total SPL levels in the stadium, further improvements to AL cons %values have been left for future
work.
Existing Coliseum Coliseum redesign-1 Coliseum redesign-2 setup-1 Coliseum redesign-2 setup-2
Maximum 100 100 100 100
Minimum 1 1.68 1.04 2.52
Average 7.97 23.72 14.12 14.41
Student section-1 1.3 5.62 3.12 11.54
Student section-2 2.3 11.39 6.35 11.17
General Public-1 14.89 36.21 24.26 12.15
General Public-2 7.69 17.26 10.79 12.72
Titantron-1 11.94 29.76 18.74 20.53
Titantron-2 7.68 16.73 10.8 12.48
Southwest corner 14.74 30.28 19.26 21.65
Press Box-1 5.33 16.75 9.37 11.34
Table 6.4-27 Los Angeles Memorial Coliseum EASE simulation comparison of Articulation loss of consonants at listeners seats
Figure 6.4-8 Los Angeles Memorial Coliseum EASE simulation comparison of Articulation loss of consonants
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6.4.7 Speech Transmission Index
Speech Transmission Index measures the quality of speech transferred from speaker to listener (ADA
(Acoustic Design Anhert), 2009). It is an index value and ranges from 0-1. A STI of 0.75 to 1 is considered
excellent. 0.6 to 0.75 is considered good. 0.45 to 0.6 is considered fair. 0.3 to 0.45 is considered poor. STI values
below 0.3 are unacceptable (ADA (Acoustic Design Anhert), 2009). EASE calculated the speech transmission index
at 7 locations namely Student section-1, Student section-2, General audience-1, General audience-2, titantron,
North-west corner, Away fans. The results from the simulations are exported as a table with the overall peak,
average and minimum speech transmission index with the speech transmission index for each location (Table 6.4-
28) (Fig 6.4-9).
Speech Transmission Index values are in acceptable range for the existing Coliseum. Coliseum redesign-1
had a poor average STI values. Coliseum redesign-2 setup-1 had the similar acoustic setup as the redesign -1 with a
partial roof system. Adding a partial roof system improves the average STI values by 0.22 which is almost 22%.
The Coliseum redesign-2 setup-2 which had an evenly spread out speaker system had all the values in the fair range
(0.45-0.6). There was a minor drop in the average values from 0.535 to 0.462 between the two setups. Since the
study focused on improving the total SPL levels in the stadium, further improvements to STI values have been left
for future work.
Existing Coliseum Coliseum redesign-1 Coliseum redesign-2 setup-1 Coliseum redesign-2 setup-2
Maximum 0.978 0.852 0.94 0.778
Minimum 0 0 0 0
Average 0.602 0.319 0.535 0.462
Student section-1 0.899 0.63 0.738 0.497
Student section-2 0.795 0.499 0.607 0.503
General Public-1 0.45 0.286 0.36 0.487
General Public-2 0.572 0.423 0.509 0.479
Titantron-1 0.491 0.322 0.408 0.391
Titantron-2 0.572 0.428 0.509 0.482
Southwest corner 0.452 0.319 0.402 0.381
Press Box-1 0.639 0.428 0.535 0.5
Table 6.4-28 Los Angeles Memorial Coliseum EASE simulation comparison of speech transmission index at listeners seats
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Figure 6.4-9 Los Angeles Memorial Coliseum EASE simulation comparison of speech transmission index
6.4.8 EASE features
EASE was used to simulate the acoustic conditions of the Los Angeles Memorial Coliseum based on field
study observations. it was noticed that EASE can only simulate acoustic conditions with only constant ambient noise
throughout the space which was not the same with the Coliseum. The student section with the in-game chants were
always noisier than the other audience stands where most of the people just sit and watch the game. To overcome
this, two scenarios had to considered for simulation with one during the normal game play and other during exciting
in game moments such as USC touchdown, interception, sack etc. The only difference between the two scenarios
were in the SPL calculations while the other values were similar.
EASE was difficult to learn and was only used in the latter part of the research timeframe. Using EASE
earlier for the study could have helped fine tune the simulation results with better results. EASE is designed to
evaluate the acoustical performance of a closed space such as lecture halls, concert halls with its sophisticated
database.
6.4.9 Takeaways from the design modification analysis of the Los Angeles Memorial Coliseum using EASE
EASE simulated four different iterations of the Coliseum namely existing, redesign-1, redesign-2 setup-1,
redesign-2 setup-2. The existing Coliseum EASE model was developed based on the current existing conditions of
the Coliseum and the field study data was used to develop the simulation settings and validate.
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It was noticed that EASE can only simulate acoustic conditions with only constant ambient noise. In order
to calculate the difference in audience response between a normal play and touchdown each simulation setup had
two scenarios defined for calculations. Scenario-1 had the speakers set to default SPL values and the input values for
ambient noise were used from the field study data collected during the course of play. Scenario-2 had all the
speakers set to the highest SPL values and input values for ambient noise were used from the field study data
collected during moments such as USC touchdown, interception by USC etc. which garnered audience response and
higher SPL values.
The SPL values calculated by the two scenarios were different while the clarity measurements (C7, C50,
C80), first arrival timings, articulation loss of consonants, speech transmission index (STI) were similar for both
scenarios calculated by EASE.
After describing the results in their respective sections, the results from all four iterations were grouped to
evaluate their performance and draw comparison.
Total SPL was calculated in two scenarios for all four iterations. Total SPL comparison at scenario-1
showed that the Coliseum redesign-2 setup-2 which had the partial roof system and a reconfigured speaker system
had higher SPL values in all the audience stands and higher overall average SPL in the stadium.
Coliseum redesign-2 setup-2 had the highest total SPL of all the iterations in the scenario-2 simulations.
The partial roof system coupled with the distributed speaker system improved the total SPL levels with the highest
SPL values recorded at 112.92 dB which does not exceed the OSHA (Occupational Safety and Health
Administration) SPL limits of 115dB in a sports arena.
C7 value results showed that the Coliseum redesign-2 setup-2 had all the C7 values at audience seats in the
acceptable value range followed by the existing Coliseum setup which had most parts of the audience seat C7 values
in the acceptable value range.
C50 value results which are based on speech clarity showed that the existing Coliseum had better overall
average C50 values. The existing speaker setup is focused on the north east and south east quadrants of the stadium
with sections 9-12 & sections 15-19 (south west & northwest corner) having unacceptable C50 values.
Mappings of C80 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. The Coliseum redesign setup-2 with
the reconfigured speaker systems had a evenly spread out mapping with several parts of the stadium with acceptable
316
C80 values without much range of values compared to the existing Coliseum but still the values were below the
acceptable range. It is difficult to maintain C80 values for a large arena within the acceptable range.
Existing Coliseum conditions had acceptable AL cons % values and the Coliseum redesign-2 setup-2 had
acceptable AL cons %values in all audience stands except for Titantron-1 and southwest corner. This acoustical
deficiency can be fixed by placing the speaker systems even closer to the audience however the study focused on
improving the total SPL levels in the stadium, further improvements to AL cons %values have been left for future
work.
Speech Transmission Index values are in acceptable range for the existing Coliseum. Coliseum redesign-1
had a poor average STI values. Coliseum redesign-2 setup-1 had the similar acoustic setup as the redesign -1 with a
partial roof system. Adding a partial roof system improves the average STI values by 0.22 which is almost 22%. The
Coliseum redesign-2 setup-2 which had an evenly spread out speaker system had all the values in the fair range
(0.45-0.6). There was a minor drop in the average values from 0.535 to 0.462 between the two setups.
Based on the analysis all the four iterations namely existing Coliseum, Coliseum redesign-1, Coliseum
redesign setup-1 and Coliseum redesign setup-2 have been ranked in terms of performance.
The Existing Coliseum tends to perform well only in overall average of C50, C80, Articulation loss of
consonants and STI marginally than others due to the speaker systems placed closer to several parts of the audience
section.
The Coliseum redesign-2 performs well in the critical metrics such as the Total SPL and the first arrival
timings due to its evenly spread speaker system. It means all the seats in this setup have more or less the same
acoustic quality than the other setups which have several parts performing well acoustically and several parts
performing poorly (Table 6.4-29). This iteration was set as a benchmark over the other iterations.
A future retrofit with a partial roof system and an evenly spread speaker system will prove to be useful for
the Los Angeles Memorial Coliseum as it looks to host the 2028 Olympics. The other metrics where the current
proposed iteration of the Coliseum can be finetuned to perform even better with more time.
317
Acoustic Parameter
Existing Coliseum
Coliseum
redesign-1
Coliseum redesign-2
setup-1
Coliseum redesign-2
setup-2
Total SPL scenario-1 4 3 2 1
Total SPL scenario-2 4 3 2 1
C7 2 3 4 1
C50 1 4 3 2
C80 1 4 2 3
First Arrival 2 2 2 1
Articulation loss of
consonants
1 4 2 3
Speech Transmission
Index
1 4 2 3
Table 6.4-29 Los Angeles Memorial Coliseum performance ranking of all iterations by acoustic metrics
6.5 Summary
Following the analysis of the Los Angeles Memorial Coliseum, it was concluded that the noise generated
by audience is lesser compared to other sports arenas. Two design options are proposed, and an acoustic analysis of
the design options were made to look for any improvement in overall acoustic quality. The first option was the new
proposed redesign of the Los Angeles Memorial Coliseum. The second option had a partial roof system over the
northern and southern stands. Both the proposed options are simulated in EASE and analyzed to look for any
improvements.
A partial roof system was added to the north and south stands of the design modification -1. The partial
roof was designed to trap the sound inside the stadium reflect the audience noise towards the pitch. ETFE (Ethylene
tetrafluoroethylene) was considered for roof material for its light weight and reflective properties. ETFE has been
used for stadium facades and roof systems for the same reasons. The structural system to support the roof system has
not been discussed as the study only focuses on the acoustical analysis and the improvement the roof system
provides over existing conditions.
Two setups were considered for the redesign-2 with the first setup consisting of the existing speaker setup
in the stadium. Setup-2 had an alternate speaker layout with the speakers focusing on the audience stands form the
partial roof system. Two scenarios were considered while simulating the acoustic conditions of the Coliseum. The
318
input for ambient noise varied in both the scenarios which are taken from the field study data collected at the
Coliseum during the 2017 football season.
EASE was used to simulate the acoustic conditions of the Los Angeles Memorial Coliseum based on field
study observations. it was noticed that EASE can only simulate acoustic conditions with only constant ambient noise
throughout the space which was not the same with the Coliseum. The student section with the in-game chants were
always noisier than the other audience stands where most of the people just sit and watch the game. To overcome
this, two scenarios had to considered for simulation with one during the normal game play and other during exciting
in game moments such as USC touchdown, interception, sack etc. The only difference between the two scenarios
were in the SPL calculations while the other values were similar.
Scenario-1 mappings of total sound pressure level (SPL) EASE simulation mappings of Coliseum,
Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw
comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the reconfigured speaker
system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had higher SPL values than
the existing Coliseum due to the presence of the enlarged glass box in the press box which reflected the audience
noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed to contain the sound
and reflect it within the stadium which resulted in higher SPL values.
Scenario-2 mappings of total sound pressure level (SPL) EASE simulation mappings of Coliseum,
Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw
comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the reconfigured speaker
system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had higher SPL values than
the existing Coliseum due to the presence of the enlarged glass box in the press box which reflected the audience
noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed to contain the sound
and reflect it within the stadium which resulted in higher SPL values. Coliseum redesign-2 setup-1 had the existing
speaker setup which calculated the highest SPL from the student section mapping area which is closer to the USC
band speaker systems. Coliseum redesign-2 setup-1 & setup-2 had the highest SPL values of 114.5 dB and 112.92
dB respectively. Mapping comparison shows that the Coliseum redesign-2 setup-2 has an consistent spread of SPL
values throughout the Coliseum which was the design intent.
319
Mappings of C7 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. Results comparison show that
Coliseum redesign-2 setup-1 has more of the values in the acceptable range for most of the frequency range. C7
simulation results show that the aaverage C7 values in Coliseum redesign-2 setup-2 with the reconfigred speaker
system have all values in the accepable range. Average C7 values at the existing Coliseum are in the acceptable
range with a parts of the audience stands having unacceptable values.
Mappings of C50 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. Results comparison show that
Coliseum redesign-2 setup-1 has more of the values in the acceptable range for most of the frequency range.
Existing Coliseum conditions have several parts of the stadium which have acceptable speech clarity measurements
while the Coliseum redesign-2 setup-2 which had an even spread of speaker systems had C50 values which are
below the acceptable range. This acoustical deficiency can be fixed by placing the speaker systems even closer to
the audience however the study focused on improving the total SPL levels in the stadium, further improvements to
speech clarity have been left for future work.
Mappings of C80 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. The Coliseum redesign setup-2 with
the reconfigured speaker systems had a evenly spread out mapping with several parts of the stadium with acceptable
C80 values without much range of values compared to the existing Coliseum but still the values were below the
acceptable range. It is difficult to maintain C80 values for a large arena within the acceptable range. Since the study
focused on improving the total SPL levels in the stadium, further improvements to musical clarity have been left for
future work.
EASE simulation mapping shows the sound takes longer to reach the stands higher up the stadium which
explain the lower SPL values. Student sections are in the closer proximity to the speaker systems which had the
highest SPL values recorded in the field study and the EASE simulation results. Coliseum redesign-2 setup-2 which
had a reconfigured speaker system had average first arrival times reduced by 50 microseconds throughout the
stadium. Decreasing the first arrival timings by spreading out speaker systems made the total SPL values higher in
the stadium.
320
Existing Coliseum conditions had acceptable AL cons % values and the Coliseum redesign-2 setup-2 had
acceptable AL cons %values in all audience stands except for Titantron-1 and southwest corner. This acoustical
deficiency can be fixed by placing the speaker systems even closer to the audience however the study focused on
improving the total SPL levels in the stadium, further improvements to AL cons %values have been left for future
work.
Speech Transmission Index values are in acceptable range for the existing Coliseum. Coliseum redesign-1
had a poor average STI values. Coliseum redesign-2 setup-1 had the similar acoustic setup as the redesign -1 with a
partial roof system. Adding a partial roof system improves the average STI values by 0.22 which is almost 22%.
The Coliseum redesign-2 setup-2 which had an evenly spread out speaker system had all the values in the fair range
(0.45-0.6). There was a minor drop in the average values from 0.535 to 0.462 between the two setups. Since the
study focused on improving the total SPL levels in the stadium, further improvements to STI values have been left
for future work.
Based on the analysis all the four iterations namely existing Coliseum, Coliseum redesign-1, Coliseum
redesign setup-1 and Coliseum redesign setup-2 have been ranked in terms of performance. The Existing Coliseum
tends to perform well only in overall average of C50, C80, Articulation loss of consonants and STI marginally than
others due to the speaker systems placed closer to several parts of the audience section.
The Coliseum redesign-2 performs well in the critical metrics such as the Total SPL and the first arrival
timings due to its evenly spread speaker system. It means all the seats in this setup have more or less the same
acoustic quality than the other setups which have several parts performing well acoustically and several parts
performing poorly (Table 6.5-1). This iteration was set as a benchmark over the other iterations.
Acoustic Parameter Existing Coliseum Coliseum redesign-1 Coliseum redesign-2 setup-1 Coliseum redesign-2 setup-2
Total SPL scenario-1 4 3 2 1
Total SPL scenario-2 4 3 2 1
C7 2 3 4 1
C50 1 4 3 2
C80 1 4 2 3
First Arrival 2 2 2 1
Articulation loss of consonants 1 4 2 3
Speech Transmission Index 1 4 2 3
Table 6.5-1 Los Angeles Memorial Coliseum performance ranking of all iterations by acoustic metrics
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A future retrofit with a partial roof system and an evenly spread speaker system will prove to be useful for
the Los Angeles Memorial Coliseum as it looks to host the 2028 Olympics. The other metrics where the current
proposed iteration of the Coliseum falls short can be finetuned to perform even better with more time. The
shortcomings faced in the study and possible future studies are described in chapter 7.
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Chapter 7: Conclusion & Future Work
7.1 Overview
Acoustic performance of a stadium can be simulated and validated by first performing a field study and
then comparing with simulated results. With trust established in the software, design changes can be made virtually
to predict the performance if the changes were to be implement. The Los Angeles Memorial Coliseum is taken as
the case study. The Coliseum was visited during the USC Trojans football season 2017-18 to collect data during the
football games. For simplification purposes in developing the Dynamo script, the Harris Hall courtyard at University
of Southern California was as the first case study for its similarity to the Coliseum in terms of spatial configuration.
Both the spaces are enclosed on the sides with open to sky in the middle.
7.2 Acoustic simulation and field study process used for the study
Audix TM-1, Rolland Octacapture, Yamaha Stagepas 400i, Bruel & Kjaer type 2250 are acoustic
measurement equipment used for the acoustic field study at Harris Hall courtyard at University of Southern
California. EASERA program was used to record the data and perform the analysis with the equipment. Extech HD
600 and Sound Analyzer app are studied to learn about their usage and were used to record data during the home
football games at the Los Angeles Memorial Coliseum during the 2017-18 college football season. EASE was used
to simulate acoustics on Harris Hall courtyard and Los Angeles Memorial Coliseum. Harris Hall courtyard was
modelled in Revit to develop the Dynamo script for simulating acoustics. EASE was used to validate the results
from the Dynamo script and the field study. EASE was used perform the acoustic simulation for the design
modification analysis of the Los Angeles Memorial Coliseum.
7.2.1 Dynamo
The Harris Hall courtyard was modeled in Revit. The materials and finishes were applied and made as
accurate as possible. An instant parameter was added to the material with the “absorption” values. Eight parameters
were added for every frequency in the one-third octa band (125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz,
8000 Hz). Measures were taken to keep the Revit model free of any errors.
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The Dynamo script was divided into four parts: Revit data extraction, defining analysis grid and dividing
extracted surfaces into grids, defining the sound sources, and the ray trace analysis:
The first part extracted the surfaces and the material properties from the Revit model. All the extracted
surfaces (walls, floors, doors) are split into grids and made into a list in Dynamo. The output of these nodes showed
the surfaces in the Revit model on Dynamo workspace.
The second part of the script created a 3-dimensional grid over the entire model. The limits of the grids
were set in a way to make sure that the Revit model is fully inside the grid. The surfaces extracted in the previous
part were divided into grids to serve as the bounce off points during ray-trace function.
The third part of the script defined the point sound sources in the study. The Harris Hall courtyard acoustic
study had two sound sources. Each point source is defined by the following parameters. Sound pressure level (SPL)
based on one third octa band frequency (125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz, 8000 Hz), location
of the source as a point, direction of the sound source by defining a vector towards the target point from the source
point, number of bounces and the parameters to export the data as an Excel sheet.
The fourth part of the Dynamo script performed the ray trace analysis and the acoustic simulation in the
Revit model. The ray trace methodology used the principle of geometric acoustics (GA) where the rays are assumed
to carry sound energy and behave similar to light rays. Each point source projected a cone towards the direction
vector given in the node (Fig 7.2-1). Similarly, after refection from the surfaces, cones were projected towards the
normal vector direction of the incoming vector. The sound pressure levels were calculated on each point separately
in the 3-dimensional grid. A list was created for a point in the grid. The list had sound pressure levels as the inputs
after each bounce. For direct sound pressure level, the SPL at the point was directly calculated. When there were
multiple sources, the direct SPL is calculated by adding the SPL from all sources at the point. It should also be noted
that SPL levels decrease through distance. When a point source projects a cone, the SPL levels were added to the list
of SPL values to the points that fall within the volume of the cone. After the cone reached a wall or floor surface
where it is subject to reflection, the points in the wall act where the cone falls acted as starting points for the first
bounce. Each point where the cone falls acted as the starting point with the respective vector based on the incoming
vector from the source location will be the direction vector for the next sequence.
A cone was projected from the points on the wall or floor surfaces where the direct sound rays fell during
the first sequence of ray tracing towards the normal direction of the incoming rays. The list of points on which the
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projected cones fall were filtered using the “Geometry.doesintersect” node. A test was created to check if the point
falls within the cone. True would return the sound pressure level at the point for this sequence and false returns zero.
When the ray reached the point on the floor or wall, the SPL level at the point was calculated. Before the start of
next sequence (bounce 1) the SPL level was again calculated, which would have reduced based on the absorption
coefficient (α) of the respective surface. The calculated SPL at the point after reflection or absorption becomes the
incident SPL for the next sequence. The same sequence followed based on the number of bounces given in the input.
Every time a point fell within the projected cone(s), the corresponding sound pressure level (SPL) at the point was
added to the list. After the completion of the full ray-trace sequence, each calculation point had several sound
pressure level (SPL) values, which were added to the list every time the point was inside the cone. The SPL values
were added together logarithmically, and the output was exported as an excel spreadsheet with the corresponding
coordinates.
Figure 7.2-1 Dynamo Script showing projection of cone from the point source locations during direct sound projection sequence
The above sequence is for calculation of the total SPL at a point for one frequency. The same process is
repeated for the other frequency values, and the output is exported as an Excel spreadsheet.
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Figure 7.2-2 Harris Hall courtyard Dynamo script methodology
After the development of the Dynamo script for running the acoustic simulation on Revit models, the
script crashed due to the instability of the software, which could not handle the complex calculations associated with
the ray tracing algorithm. The results turned out to be suspiciously similar to each other even after trying several
methods of simplifying the script to perform the same set of calculations. It was concluded that the current version
of Dynamo cannot handle the complexity of the script. Therefore, the methodology was updated to focus on the
acoustic simulation analysis of the Los Angeles Memorial Coliseum and come up with two design options which
could provide a better overall acoustic experience.
7.2.2 EASE
EASE supports importing geometry from DXF and SKP (Sketchup) formats. The Revit model of the
Coliseum had more surfaces which would have taken longer for computation. Hence a simplified model of the
Coliseum was made in AutoCAD and was exported as a DXF file (Fig 7.3-2). The curvilinear surfaces were
simplified into planar polygons to reduce the complexity of the geometry and reduce simulation times. The DXF file
was then opened in Sketchup to eliminate the unnecessary surfaces. All the surfaces that did not receive any
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reflections were eliminated to expedite the computing process during simulations. The model was simplified to the
minimum and exported as a Sketchup8 file which is the format supported by EASE.
The materials were applied on the Sketchup model as that made it easier to apply materials on EASE. The
Sketchup model was purged to remove any unnecessary lines, objects, and reduce the file size. The model was
exploded to sure that it becomes a single piece than several groups or components in Sketchup. After exploding the
model, the “intersect faces” option was chosen to make sure that all the faces are connected to each other. Failing to
perform this step will result in finding holes in the model when imported into EASE.
Figure 7.2-3 Workflow from AutoCAD to EASE
7.3 Case study spaces for simulating acoustics
Harris Hall courtyard at University of Southern California and the Los Angeles Memorial Coliseum were
used as the study spaces for conducting an acoustic fields study.
7.3.1 Harris Hall courtyard at University of Southern California
The Harris Hall courtyard at the University of Southern California was chosen as a case study for its
similarity to a stadium which is open to air with enclosures on four sides (Fig 7.3-1). The courtyard was modelled in
Revit and a Dynamo script was developed to run an acoustic simulation. The Harris Hall courtyard space was
exported as an AutoCAD 3d drawing and imported in Sketchup. Acoustic conditions were simulated using acoustic
software EASE. The results from Dynamo script are validated using the results from EASE and the acoustic field
study.
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Figure 7.3-1 Harris Hall courtyard at University of Southern California
7.3.2 Los Angeles Memorial Coliseum
The Los Angeles Memorial Coliseum serves as the home to the University of Southern California college
football team (USC Trojans) and the temporary home to the Los Angeles Rams of the National Football League
(NFL). An acoustic field study was conducted during the college football season of USC Trojans. The stadium has a
seating capacity of 93,607 for the football games (Fig 7.3-2). The Coliseum has also hosted the summer Olympics
twice in 1932 and 1984 (Los Angeles Memorial Coliseum, 2017). Similarly, the Los Angeles Memorial Coliseum
was simulated using EASE to analyze the acoustic performance. Based on the observations from the simulation and
field studies two design modifications were proposed. The results from the study were explained in section 4.3. The
observations and inferences from the study were explained in section 5.3.
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Figure 7.3-2 Los Angeles Memorial Coliseum during the college football game
Based on the observations and inferences, two design modifications were proposed, and the design
modification analysis of the Los Angeles Memorial Coliseum is described in chapter 0. Los Angeles Memorial
Coliseum is currently under renovation with the construction work set to take over 2 periods of 8 months with the
2018 college football season in between (Los Angeles Memorial Coliseum, 2017). The renovation project is
expected to be completed by the start of 2019 football season (Los Angeles Memorial Coliseum, 2017). The seating
capacity will be reduced from 93,607 to 77,500 (Los Angeles Memorial Coliseum, 2017).
S.No Date Start
of play (PT)
Opponent Home/Away Final
score
Attendance
1. 09/02/2017 02:15 PM Western Michigan Home 49-31 61125
2. 09/09/2017 05:30 PM Stanford Cardinals Home 42-24 77614
3. 09/16/2017 05:30 PM Texas Longhorns Home 27-24 84714
4. 09/23/2017 12:30 PM California Golden Bears Away 30-20 46747
5. 09/29/2017 07:30 PM Washington State Away 27-30 33773
6. 10/07/2017 01:00 PM Oregon State Beavers Home 38-10 60314
7. 10/14/2017 05:00 PM Utah Utes Home 28-27 72382
8. 10/21/2017 04:30 PM Notre Dame Away 14-49 77622
9. 01/28/2017 07:45 PM Arizona State Away 48-17 53446
10. 11/04/2017 07:45 PM Arizona Wildcats Home 49-35 70225
11. 11/11/2017 01:00 PM Colorado Away 38-24 49337
12. 11/18/2017 05:00 PM UCLA Bruins Home 28-23 82407
Table 7.3-1 USC Trojans college football 2017-18 season schedule and results (University of Southern California Athletics,
2018)
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7.4 Takeaways from Harris Hall courtyard and Los Angeles Memorial Coliseum field study and EASE
simulation
The main purpose of conducting the acoustic field study at Harris Hall courtyard was for its similarity to a
stadium space with similar spatial configuration (open to sky with enclosed on sides) on a smaller scale. The field
study was not conducted with the notion of analyzing the space and the speaker placement configurations and
evaluate the acoustic conditions. The primary intent was to develop a Dynamo script to calculate all the acoustical
parameters. The speaker systems were placed in the study to maximize reflections so that the acoustic parameters
can be calculated using Dynamo. It was first tested by comparing real data from measurements in Harris Hall
courtyard to the simulation. The acoustic simulation of the courtyard provided slightly higher sound levels results
than the acoustic field study data, which is probably due to the presence of trees in the courtyard that could not be
modeled in the EASE model. There was sufficient data to conduct a detailed analysis but however the focus of the
study is concentrated on the Los Angeles Memorial Coliseum and the retrofit study and the Harris Hall courtyard
data can be used as a ground work for developing and valuating the Dynamo which is included in the possible future
study scope in chapter 7.
An acoustic field study was conducted during the 2017-18 college football season at the Los Angeles
Memorial Coliseum. Data collection from the field study at the Los Angeles Memorial Coliseum showed that the
Total SPL values recorded are not as high as it should be for a stadium with a capacity of 93500. Results showed
that the game against Texas Longhorns and the UCLA bruins recorded the highest sound pressure values due to the
higher stadium attendance. Both the games were played in the evening which had the larger crowd stay till the end
of the game. The Texas game went into extra time and had more exciting moments which had an influence on the
SPL values. Given the rivalry between USC Trojans and UCLA Bruins, the game had more excitement among the
audience and it was the last game of the season which resulted in higher SPL noises in the audience stands. The
game against Western Michigan despite being the season opener had a very low attendance due to the early kick off
time (02:15 PM) on a summer afternoon. Similarly, the Oregon State Beavers game also had similar attendance due
to the early kick off time (01:00 PM). Highest recorded value was 99.31 dB at the student section-1 and lowest
recorded value was 65.87 dB at the student section-2. Major reason for such lower SPL values is the absence of a
roof system which would help reflect the noise towards the pitch and to other audience stands which in turn would
make the audience cheer even more thereby increasing the overall SPL levels in the stadium. Also, the distribution
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of the speaker systems is found to be inefficient as it does not reach the farther stands in the stadium. A retrofit with
a roof and a reconfigured sound system would improve the acoustic performance of the stadium.
Los Angeles Memorial Coliseum was simulated in EASE. The results from EASE simulation are described
below. Two scenarios were considered while simulating the acoustic conditions of the Coliseum. The input for
ambient noise varied in both the scenarios which are taken from the field study data collected at the Coliseum during
the 2017 football season. Scenario-1 calculated the Total SPL at lower ambient noise level. The mapping shows the
SPL levels are higher at the audience stands closer to the speaker systems. The placement of speaker systems played
a critical role in overall SPL values. EASE simulation mapping showed the audience stands closer to the speaker
systems had a higher SPL values which was similar to the field study observations. Possible reason for this was the
absence of a roof system which would have reflected the sound towards the audience stands and pitch.
The audience sections located farther from the speakers have unacceptable C7, C50, C80, AL cons
percentages, STI values as highlighted in the results and the mapping. The Titantron speakers are directed towards
the eastern end of the pitch which means the sound received in these stands are reflections from other stands. The
acoustic deficiencies can be fixed by reconfiguring the speaker system to distribute sound equally towards the
stands.
EASE was used to simulate the acoustic conditions of the Los Angeles Memorial Coliseum based on field
study observations. it was noticed that EASE can only simulate acoustic conditions with only constant ambient noise
throughout the space which was not the same with the Coliseum. The student section with the in-game chants were
always noisier than the other audience stands where most of the people just sit and watch the game. To overcome
this, two scenarios had to considered for simulation with one during the normal game play and other during exciting
in game moments such as USC touchdown, interception, sack etc. The only difference between the two scenarios
were in the SPL calculations while the other values were similar.
Based on the analysis, two design retrofit options were proposed. First option is based on the proposed
renovation of the Coliseum. The second option has a partial roof system over the north and south stands in the
proposed renovation and a reconfigured speaker system were explained in chapter 6.
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7.5 Design modification analysis study of the Los Angeles Memorial Coliseum
Following the analysis of the Los Angeles Memorial Coliseum, it was concluded that the noise generated
by audience is lesser compared to other sports arenas. Two design options are proposed, and an acoustic analysis of
the design options are made to look for any improvement in overall acoustic quality. The first option will be the new
proposed redesign of the Los Angeles Memorial Coliseum. The second option will have a partial roof system over
the northern and southern stands. Both the proposed options are simulated in EASE and analyzed to look for any
improvements.
A partial roof system was added to the north and south stands of the design modification -1. The partial
roof was designed to trap the sound inside the stadium reflect the audience noise towards the pitch. ETFE (Ethylene
tetrafluoroethylene) was considered for roof material for its light weight and reflective properties. ETFE has been
used for stadium facades and roof systems for the same reasons. The structural system to support the roof system has
not been discussed as the study only focuses on the acoustical analysis and the improvement the roof system
provides over existing conditions.
Two setups were considered for the redesign-2 with the first setup consisting of the existing speaker setup
in the stadium. Setup-2 had an alternate speaker layout with the speakers focusing on the audience stands form the
partial roof system. Two scenarios were considered while simulating the acoustic conditions of the Coliseum. The
input for ambient noise varied in both the scenarios which are taken from the field study data collected at the
Coliseum during the 2017 football season.
Scenario-1 mappings of total sound pressure level (SPL) EASE simulation mappings of Coliseum,
Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw
comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the reconfigured speaker
system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had higher SPL values than
the existing Coliseum due to the presence of the enlarged glass box in the press box which reflected the audience
noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed to contain the sound
and reflect it within the stadium which resulted in higher SPL values.
Scenario-2 mappings of total sound pressure level (SPL) EASE simulation mappings of Coliseum,
Coliseum redesign-1, Coliseum redesign-2 setup-1, Coliseum redesign setup-2 were grouped together to draw
comparison. EASE simulation results show that the Coliseum redesign-2 setup-2 with the reconfigured speaker
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system have higher SPL levels compared to the existing Coliseum. Coliseum redesign-1 had higher SPL values than
the existing Coliseum due to the presence of the enlarged glass box in the press box which reflected the audience
noise inside the stadium. Coliseum redesign-2 had a partial roof system which was designed to contain the sound
and reflect it within the stadium which resulted in higher SPL values. Coliseum redesign-2 setup-1 had the existing
speaker setup which calculated the highest SPL from the student section mapping area which is closer to the USC
band speaker systems. Coliseum redesign-2 setup-1 & setup-2 had the highest SPL values of 114.5 dB and 112.92
dB respectively. Mapping comparison shows that the Coliseum redesign-2 setup-2 has an consistent spread of SPL
values throughout the Coliseum which was the design intent.
Mappings of C7 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. Results comparison show that
Coliseum redesign-2 setup-1 has more of the values in the acceptable range for most of the frequency range. C7
simulation results show that the aaverage C7 values in Coliseum redesign-2 setup-2 with the reconfigred speaker
system have all values in the accepable range. Average C7 values at the existing Coliseum are in the acceptable
range with a parts of the audience stands having unacceptable values.
Mappings of C50 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. Results comparison show that
Coliseum redesign-2 setup-1 has more of the values in the acceptable range for most of the frequency range.
Existing Coliseum conditions have several parts of the stadium which have acceptable speech clarity measurements
while the Coliseum redesign-2 setup-2 which had an even spread of speaker systems had C50 values which are
below the acceptable range. This acoustical deficiency can be fixed by placing the speaker systems even closer to
the audience however the study focused on improving the total SPL levels in the stadium, further improvements to
speech clarity have been left for future work.
Mappings of C80 EASE simulation mappings of Coliseum, Coliseum redesign-1, Coliseum redesign-2
setup-1, Coliseum redesign setup-2 were grouped together to draw comparison. The Coliseum redesign setup-2 with
the reconfigured speaker systems had a evenly spread out mapping with several parts of the stadium with acceptable
C80 values without much range of values compared to the existing Coliseum but still the values were below the
acceptable range. It is difficult to maintain C80 values for a large arena within the acceptable range. Since the study
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focused on improving the total SPL levels in the stadium, further improvements to musical clarity have been left for
future work.
EASE simulation mapping shows the sound takes longer to reach the stands higher up the stadium which
explain the lower SPL values. Student sections are in the closer proximity to the speaker systems which had the
highest SPL values recorded in the field study and the EASE simulation results. Coliseum redesign-2 setup-2 which
had a reconfigured speaker system had average first arrival times reduced by 50 microseconds throughout the
stadium. Decreasing the first arrival timings by spreading out speaker systems made the total SPL values higher in
the stadium.
Existing Coliseum conditions had acceptable AL cons % values and the Coliseum redesign-2 setup-2 had
acceptable AL cons %values in all audience stands except for Titantron-1 and southwest corner. This acoustical
deficiency can be fixed by placing the speaker systems even closer to the audience however the study focused on
improving the total SPL levels in the stadium, further improvements to AL cons %values have been left for future
work.
Speech Transmission Index values are in acceptable range for the existing Coliseum. Coliseum redesign-1
had a poor average STI values. Coliseum redesign-2 setup-1 had the similar acoustic setup as the redesign -1 with a
partial roof system. Adding a partial roof system improves the average STI values by 0.22 which is almost 22%.
The Coliseum redesign-2 setup-2 which had an evenly spread out speaker system had all the values in the fair range
(0.45-0.6). There was a minor drop in the average values from 0.535 to 0.462 between the two setups. Since the
study focused on improving the total SPL levels in the stadium, further improvements to STI values have been left
for future work.
EASE was used to simulate the acoustic conditions of the Los Angeles Memorial Coliseum based on field
study observations. it was noticed that EASE can only simulate acoustic conditions with only constant ambient noise
throughout the space which was not the same with the Coliseum. The student section with the in-game chants were
always noisier than the other audience stands where most of the people just sit and watch the game. To overcome
this, two scenarios had to considered for simulation with one during the normal game play and other during exciting
in game moments such as USC touchdown, interception, sack etc. The only difference between the two scenarios
were in the SPL calculations while the other values were similar.
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EASE was difficult to learn and was only used in the latter part of the research timeframe. Using EASE
earlier for the study could have helped fine tune the simulation results with better results. EASE is designed to
evaluate the acoustical performance of a closed space such as lecture halls, concert halls with its sophisticated
database.
7.6 Takeaways from the design modification analysis of the Los Angeles Memorial Colseum
The existing Coliseum had several parts of the stadium with good acoustics while the other parts were
severely affected by the poor placement of the speakers. Sections 8-12 and 16-20 which are the southwest and
northwest corners of the stadium respectively received very little direct sound from the speaker systems resulting in
lower SPL values that can be seen evidently in the field study and EASE simulation results.
While the primary intent of the study was to improve the total sound pressure levels in the Coliseum, EASE
had the capabilities to calculate other metrics such as Clarity (C7, C50 & C80) measurements, articulation loss of
consonants, speech transmission index which help fine tune the acoustic performance of a space.
After comparing the results of the 4 iterations of the Coliseum, the Coliseum redesign-2 setup-2 with the
partial roof system and the reconfigured speaker system performs better than the other iterations in terms of Total
SPL in the stadium (Table 7.6-1). The partial roof aided in trapping the sound and redirecting it within the stadium.
The speaker systems play an important role in the retrofit. All speakers were placed along the roof system facing the
audience which resulted in faster first arrival times on all seats as seen in the first arrival mapping comparison.
Longer the arrival time, more the sound must travel which results in reduced SPL by the time it reached the
audience. Due to the multiple reflections effected by the partial roof and the reconfigured speaker system, there was
an even and consistent spread of sound throughout the stadium as seen in the total SPL mapping comparison
resulting in no bad seats which was the case in the existing Coliseum. Existing Coliseum had peak values reaching
101 dB and the proposed retrofit has improved peak values reaching 114 dB which is indicative of the improvement
in total SPL levels in the stadium (Fig 7.6-1).
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Acoustic Parameter
Existing Coliseum
Coliseum
redesign-1
Coliseum redesign-
2 setup-1
Coliseum redesign-
2 setup-2
Total SPL scenario-1 4 3 2 1
Total SPL scenario-2 4 3 2 1
C7 2 3 4 1
C50 1 4 3 2
C80 1 4 2 3
First Arrival 2 2 2 1
Articulation loss of
consonants
1 4 2 3
Speech Transmission
Index
1 4 2 3
Table 7.6-1 Los Angeles Memorial Coliseum performance ranking of all iterations by acoustic metrics
Figure 7.6-1 Los Angeles Memorial Coliseum comparison between existing and proposed retrofit
Adding a partial roof system to the existing Coliseum will only improve the acoustic performance of the
stadium. The proposed retrofit will eliminate the bad seats in the Coliseum which will bring more attendance to the
stadium. On a more commercial sense, negating the bad seats in the Coliseum can be used as an opportunity to
increase the ticket prices in those sections which will give a better experience to the audience than the existing
Coliseum. One of the major complaints about the Coliseum is that it isn’t loud enough for a stadium with a capacity
of 93500. Although the seating capacity will be reduced to 77500 with the current proposed renovation, the partial
roof retrofit has only increased the acoustic performance of the stadium. As Los Angeles and the Coliseum look
forward to hosting the 2028 Olympics, adding a partial roof retrofit will add more value to the stadium experience.
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7.7 Future work
There were several parts of the research which could not be completed in the timeframe and have been left
for future work. Several shortcomings were also found which could be improved should the research be continued
by someone in the future.
7.7.1 Acoustic simulation software
Acoustic simulation software EASE was used to simulate the acoustic conditions of the Los Angeles
Memorial Coliseum and provide two retrofit options based on the analysis. However, there were parts of the study
that could not be completed in the study timeframe and can be used as a future study.
EASE
EASE can be used to develop more future studies based on the design modification analysis of the
Coliseum.
Adding more data points in the existing study
The design modification analysis of the Coliseum had calculated acoustic parameters at 7 locations namely
Student section-1, Student section-2, General audience-1, General audience-2, titantron, North-west corner, Away
fans. Few more data points can be added, and the study can be continued to get an even thorough understanding of
the acoustic performance of the Coliseum.
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Figure 7.7-1 Los Angeles Memorial Coliseum EASE simulation additional data points
Clarity measurement study of the Los Angeles Memorial Coliseum
EASE was used to simulate the acoustic conditions of the Los Angeles Memorial Coliseum and develop
two retrofit options. The primary intent was to improve the total SPL values in the stadium which was achieved.
However, clarity measurements (C50 & C80) which are metrics for speech and music clarity respectively are lower
than the recommended values. A study can be conducted to improve the clarity metrics of the Coliseum using
EASE. There has been a detailed study on developing an acoustic simulation model using EASE in this study which
will be helpful.
7.7.2 Lighting retrofit at the Coliseum
Adding a partial roof system over the existing Coliseum would require the current stadium lighting to be
modified (Fig 7.7-2). A study to examine the possibility of adding a lighting retrofit will be a good future study.
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Figure 7.7-2 Los Angeles Memorial Coliseum lighting retrofit future study
7.7.3 Dynamo script for Harris Hall courtyard acoustic simulation
Dynamo was chosen to simulate acoustics and develop a tool that can be used with Revit to perform ray
trace analysis. Due to instability of the current Dynamo build, the script had crashed, and the focus of the study had
to be shifted to using EASE for acoustic simulation and develop two retrofit options. The results from the field study
of Harris Hall courtyard have sufficient data that can be validated by developing the Dynamo script to calculate the
acoustic parameters.
7.7.4 Pachyderm
Pachyderm was proposed as a method of validation to the results from the Dynamo script. Pachyderm can
be used to develop the Dynamo script since it is a computational design program designed to work with Grasshopper
which works similar to Dynamo.
7.7.5 Field study shortcomings and how to overcome them
There were several bottlenecks and issues that were encountered during the course of the study and have
been described in the following section.
Data collection at the Coliseum using the spider cam
An acoustic field study was conducted during the 2017-18 college football season at the Los Angeles Memorial
Coliseum. A consistent acoustic measurement data could not be achieved due to the inconsistent attendance in the
stadium through the season. All the afternoon games had lower attendance due to the afternoon warm weather
conditions in southern California. Also, the student sections saw audience leave in the second half of the afternoon
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games due to the sunny weather conditions. Data could not be collected at different locations at the same time which
would have helped under the difference in SPL levels between the audience sections. Sound pressure level
measurements could not be conducted on the Pitch due to security reasons. Data could not be collected on the Pitch
during the games. In order to collect data from the pitch without interrupting the play, a SPL meter can be used to
collect data from the spider cam. The spider cam has an in-built mic that records the player and referee
conversations. This will help us understand the total SPL levels during various course of the game. The possibility
of exploring this option can be used in the future study.
Figure 7.7-3 Spider cam used in the stadiums
Field study with modifying the Harris Hall courtyard
Harris Hall courtyard was chosen as a study space for its similarity to the stadiums in terms of spatial
configuration (enclosed on all sides with open to air). Setting up a temporary reflector surface on the side walls on
the courtyard and conducting the field study will be an interesting future study to validate the simulation results.
7.8 Conclusion
The Los Angeles Memorial Coliseum was chosen to study stadium acoustics. The Harris Hall courtyard at
University of Southern California was chosen for its similar spatial configuration and smaller scale as a case study to
340
analyze exterior acoustics and develop the tool to simulate acoustics. A Revit model of the space was made, and a
Dynamo script was developed to simulate the acoustics.
After the development of the Dynamo script for running the acoustic simulation on Revit models, the script
crashed due to the instability of the software, which could not handle the complex calculations associated with the
ray tracing algorithm. The results turned out to be similar even after trying several methods of simplifying the script
to perform the same set of calculations. It was concluded that the current version of Dynamo cannot handle the
complexity of the script. Therefore, the methodology was updated to focus on the acoustic simulation analysis of the
Los Angeles Memorial Coliseum and come up with two design options which could provide a better overall acoustic
experience. Results from acoustic field study and EASE simulations of Harris Hall courtyard and the Los Angeles
Memorial Coliseum were described in chapter 4.
There was sufficient data to conduct a detailed analysis but however the focus of the study is concentrated
on the Los Angeles Memorial Coliseum and the retrofit study and the Harris Hall courtyard data can be used as a
ground work for developing and valuating the Dynamo which is included in the possible future study
Los Angeles Memorial Coliseum was simulated in EASE. The results from EASE simulation are described
below. Two scenarios were considered while simulating the acoustic conditions of the Coliseum. The input for
ambient noise varied in both the scenarios which are taken from the field study data collected at the Coliseum during
the 2017 football season. The audience sections located farther from the speakers have unacceptable C7, C50, C80,
AL cons percentages, STI values as highlighted in the results and the mapping.
Based on the analysis, two design retrofit options were proposed. First option is based on the proposed
renovation of the Coliseum. The second option has a partial roof system over the north and south stands in the
proposed renovation and a reconfigured speaker system that were explained in chapter 6 (Fig 7.8-1).
Coliseum design modification-1 was based on the proposed renovation and a partial roof system was added
to the north and south stands of the design modification -1. The partial roof was designed to trap the sound inside the
stadium reflect the audience noise towards the pitch. ETFE (Ethylene tetrafluoroethylene) was considered for roof
material for its light weight and reflective properties. ETFE has been used for stadium facades and roof systems for
the same reasons. The structural system to support the roof system has not been discussed as the study only focuses
on the acoustical analysis and the improvement the roof system provides over existing conditions.
341
Figure 7.8-1 Los Angeles Memorial Coliseum comparison between various iterations
Two setups were considered for the redesign-2 with the first setup consisting of the existing speaker setup
in the stadium. Setup-2 had an alternate speaker layout with the speakers focusing on the audience stands form the
partial roof system.
Coliseum redesign-2 setup-1 & setup-2 had the highest SPL values of 114.5 dB and 112.92 dB
respectively. Mapping comparison shows that the Coliseum redesign-2 setup-2 has an consistent spread of SPL
values throughout the Coliseum which was the design intent.
Adding a partial roof system to the existing Coliseum will only improve the acoustic performance of the
stadium. The proposed retrofit will eliminate the bad seats in the Coliseum which will bring more attendance to the
stadium. On a more commercial sense, negating the bad seats in the Coliseum can be used as an opportunity to
increase the ticket prices in those sections which will give a better experience to the audience than the existing
Coliseum. One of the major complaints about the Coliseum is that it isn’t loud enough for a stadium with a capacity
of 93500. Although the seating capacity will be reduced to 77500 with the current proposed renovation, the partial
roof retrofit has only increased the acoustic performance of the stadium. As Los Angeles and the Coliseum look
forward to hosting the 2028 Olympics, adding a partial roof retrofit will add more value to the stadium experience.
Several possible future studies are also described in this chapter that could direct the current study to
another direction.
342
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Appendices
Appendix A: Acoustic measurement equipment data sheet
A.1 Bruel and Kjaer type 2250
Figure 0-1 Bruel & Kjaer type 2250 datasheet-1 (Bruel & Kjaer, 2018)
347
Figure 0-2 Bruel & Kjaer type 2250 datasheet-2 (Bruel & Kjaer, 2018)
348
A.2 Rolland octa capture
Figure 0-1 Rolland Octacapture datasheet (Roland Corporation, 2018)
349
A.3 Audix TM-1
Figure 0-1 Audix TM-1 datasheet-1 (Audix, 2018)
350
Figure 0-2 Audix TM-1 datasheet-2 (Audix, 2018)
351
A.4 Yamaha stagepas 400i
Figure 0-1 Yamaha stagepas 400i datasheet-1 (Yamaha Corporation, 2018)
352
Figure 0-2 Yamaha stagepas 400i datasheet-2 (Yamaha Corporation, 2018)
353
Figure 0-3 Yamaha stagepas 400i datasheet-3 (Yamaha Corporation, 2018)
354
Figure 0-4 Yamaha stagepas 400i datasheet-4 (Yamaha Corporation, 2018)
355
A.5 Extech HD600
Figure 0-1 Extech HD 600 datasheet (FLIR Systems, 2018)
356
Appendix B: Supporting data from EASERA and the field study at Harris Hall courtyard, University of
Southern California
B.1 Harris Hall courtyard field study photos
Figure 0-1 Harris Hall courtyard field study photograph-1
Figure 0-2 Harris Hall courtyard field study photograph-2
357
B.2 Revit model
Figure 0-1 Harris Hall courtyard Revit model floor plan with dimensions
358
Appendix C: Supporting data from the field study conducted during the football season at the Los Angeles
Memorial Coliseum
C.1 Photos from Coliseum
Figure 0-1 Los Angeles Memorial Coliseum post-game band performance
Figure 0-2 Los Angeles Memorial Coliseum halftime band performance
359
C.2 Excel spreadsheets from Sound Analyzer app
Sound Analyzer App: v2.2
Mode: â…“ Octave Bands / A-Weighting / Fast-Weighting (125 ms)
Unit: dBA
Last calibration:
Nov 4, 2017 -
20:39:53
Date: 4-Nov-17
Time: 8:40:21 PM
Duration (s): 24.89179
Overflow: 0
Time (s): / Midband
frequencies 63 Hz
125
Hz
250
Hz
500
Hz
1000
Hz
2000
Hz
4000
Hz
8000
Hz Global
0.09288 24.28 35.97 43.63 61.34 53.83 52.35 49.24 41.75 67.2
0.18576 26.03 37.72 46.87 60.22 56.18 53.59 48.61 43.56 68.06
0.278639 27.22 40.24 49.14 58.78 57.77 55.65 48.05 43.77 69.16
0.371519 27.77 39.63 51.39 58.5 57.16 58.1 47.32 44.61 71.29
0.464399 26.76 41.64 50.62 58.53 59.24 59.31 48.83 45.1 73.38
0.557279 29.7 40.72 50.91 57.63 61.83 63.79 50.65 46.63 74.59
0.650159 30.56 43.1 50.06 56.25 61.5 64.53 50.42 46.1 74.44
0.743039 29.84 41.55 52.24 56.17 60.15 63.91 50.38 46.13 72.98
0.835918 30.01 42.48 53.51 58.07 58.89 63.16 50.92 46.66 71.95
0.928798 29.57 42.86 53.22 60.66 57.69 61.79 51.42 47.06 71.02
1.021678 28.13 41.87 54.02 60.66 57.83 60.29 50.79 46.73 70.52
1.114558 28.54 40.33 54.57 60.07 58.42 59.23 51.75 47.2 70.39
1.207438 27.6 38.6 54.91 59.96 58.49 59.32 52.15 46.82 70.34
1.300317 27.53 41.5 53.05 60.48 60.83 60 52.52 46.88 71.82
1.393197 27.35 41.26 52.17 60.43 60.63 60.35 52.31 47.59 72.66
1.486077 27.2 44.43 52.12 59.84 60 60.84 51.49 48.55 72.84
1.578957 25.82 43.29 52.74 59.78 58.98 60.39 50.92 47.67 71.93
1.671837 26.33 46.18 52.34 58.42 58.02 60.22 50.18 46.53 70.6
1.764717 25.05 44.94 53.2 57.35 57.03 59.79 49.24 45.53 70.11
1.857596 24.67 43.25 53.48 58.61 57.74 58.83 50.08 45.52 69.77
1.950476 24.95 43.25 51.88 60.05 58.21 58.29 49.45 45.33 69.77
2.043356 27 42.21 51.44 61.35 59.52 59.16 49.11 44.97 70.58
2.136236 29.05 42.95 50.99 61.25 60.32 60.03 48.05 43.95 70.49
2.229116 28.36 43.79 50.5 60.61 59.53 59.62 47.23 43.36 69.92
2.321995 27.4 42.56 50.34 59.5 58.57 59.32 46.77 43.16 69.07
2.414875 27.62 40.79 51.36 58.74 58.98 58.62 47.12 43.24 68.94
2.507755 27.19 41.84 52.2 58.42 58.38 57.7 47.33 44.58 69.23
2.600635 26.57 41.5 51.81 57.75 59.3 58.4 47.95 44.7 69.57
2.693515 26.5 42.2 50.85 59.28 58.41 59.28 48.08 45.18 69.84
2.786395 24.9 42.12 52.75 61.04 58.27 59 49.49 47.04 70.47
2.879274 23.73 42.63 54.07 60.53 57.4 58.95 51.3 47.27 70.55
Table 0-1 Sample Excel sheet spreadsheet export from Sound Analyzer app
360
Appendix D: Additional data from EASE simulation of Los Angeles Memorial Coliseum
D.1 Sketchup model
Figure 0-1 Los Angeles Memorial Coliseum Sketchup model
D.2 EASE model
Figure 0-1 Los Angeles Memorial Coliseum EASE model
361
Appendix E: Additional data from EASE simulation of Los Angeles Memorial Coliseum redesign-1
E.1 Sketchup model
Figure 0-1 Los Angeles Memorial Coliseum design modification-1 Sketchup model
E.2 EASE model
Figure 0-1 Los Angeles Memorial Coliseum design modification-1 EASE model
362
Appendix F: Additional data from EASE simulation of Los Angeles Memorial Coliseum redesign-2
F.1 Sketchup model
Figure 0-1 Los Angeles Memorial Coliseum design modification-2 Sketchup model images
F.2 EASE model
Figure 0-1 Los Angeles Memorial Coliseum design modification-2 setup-2 EASE model
363
Appendix G: Dynamo script for Harris Hall courtyard at University of Southern California acoustic
simulation (incomplete)
G.1 Revit model
Figure 0-1 Harris Hall courtyard Revit model southwest isometric view
364
G.2 Dynamo script
The following images are exported form the last saved file before Dynamo crashed.
Figure 0-1 Harris Hall courtyard Dynamo script (incomplete)
Figure 0-2 Harris Hall courtyard Dynamo script Revit surface extraction
365
Figure 0-3 Harris Hall courtyard Dynamo script definition of sound sources
366
Figure 0-4 Harris Hall courtyard Dynamo script analysis grid
Figure 0-5 Harris Hall courtyard Dynamo script direct SPL calculation
367
Figure 0-6 Harris Hall courtyard Dynamo script Excel export function
Abstract (if available)
Abstract
A tool was developed to study the acoustics of a football stadium so that design retrofit decisions could be quickly studied. First, a courtyard space was chosen as a test case. A Revit 3d model of the space was created, and a field study was performed to gather sound decibel measurements. A Dynamo script was developed to extract the geometry, material properties, location of sound sources, data collection points, and then perform a ray trace analysis. After the development of the Dynamo script for running the acoustic simulation on Revit models, the script crashed due to the instability of the software that could not handle the complex calculations associated with the ray tracing algorithm. Even after trying several methods of simplifying the script to perform the same set of calculations, the script crashed. It was concluded that the current version of Dynamo cannot handle the complexity of the script. ❧ In order to proceed, the acoustical software EASE was chosen. It was first tested by comparing real data from measurements in Harris Hall courtyard to the simulation. The acoustic simulation of the courtyard provided slightly higher sound levels results than the acoustic field study data, which is probably due to the presence of trees in the courtyard that could not be included in the EASE model. ❧ In a second case study, acoustical data was gathered at the Los Angeles Memorial Coliseum during several football games, and a simplified digital model of the stadium was created in AutoCAD and exported to Sketchup. Acoustic conditions of the existing stadium were simulated in EASE. The results were compared to verify that the simulation was reasonable in line with the real data. Then two design options were proposed. The first option was the same being made for the ongoing Coliseum renovation. The second option has a partial roof system over the north and south stands. The results from the acoustic simulation showed that the presence of a canopy over the audience seating in the Coliseum provided reverberation with the sound directed towards the pitch that will create an intense atmosphere during the football games. The sound levels were spread evenly throughout the audience stands after reconfiguring the audio systems increased peak values up to 113 ㏈. The overall efficiency of the speaker system in the stadium also improved with the addition of the partial roof system.
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Asset Metadata
Creator
Seeralaselvan, Santhosh Kumar
(author)
Core Title
Acoustics simulation for stadium design using EASE: analyzing acoustics and providing retrofit options for the Los Angeles Memorial Coliseum
School
School of Architecture
Degree
Master of Building Science
Degree Program
Building Science
Publication Date
02/12/2019
Defense Date
04/26/2018
Publisher
University of Southern California
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Tag
acoustic simulation,Acoustics,Coliseum,EASE,OAI-PMH Harvest,Sports Arena,Stadium,stadium acoustics
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), Choi, Joonho (
committee member
), Noble, Douglas (
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)
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Tags
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stadium acoustics