Architectural Acoustics Handbook (A Title in J. Ross Publishing's Acoustic)

This full-color book contains the state-of-the-art knowledge and latest trends and developments in architectural acoustics research. This reference will play a fundamental role in the sustainable progress of architectural acoustics research and practical applications. World-renowned experts in the field from both the research and consulting communities contributed to the 15 chapters covering a wide range of sub-fields including computational modeling, noise, vibration controls, and environmental acoustics in the built environment and around buildings. With information not found anywhere else, this handbook is geared for architectural acoustics research, education in academia, and practical applications among acoustics consultants and industry engineers. It is divided into two Parts: Architectural Acoustics Essentials and Architectural Acoustics Practice. Front Cover 1 Title Page 2 Copyright 3 Contents 6 Preface 20 About the Editor 22 About the Contributors 24 Part I: Architectural Acoustics Essentials 32 Chapter 1 Computational Modeling of Room Acoustics I: Wave-Based Modeling 32 U. Peter Svensson, Jonathan Botts, and Lauri Savioja 32 1.1 Room Acoustic Modeling 32 1.2 Analytical Solutions 33 1.2.1 Parallelepipedic (Shoebox) Room 35 1.2.2 Modal Solution + Propagating Waves 35 1.2.3 Domain Matching 36 1.3 Numerical Solutions 37 1.3.1 Finite Difference Methods 37 1.3.2 Finite Element and Boundary Element Methods 39 1.3.3 Spectral Methods 39 References 39 Chapter 2 Computational Modeling of Room Acoustics II: Geometrical Acoustics 42 U. Peter Svensson, Samuel Siltanen, Lauri Savioja, and Ning Xiang 42 2.1 Unifying Frameworks of Geometrical Acoustics 42 2.1.1 Acoustic Radiative Transfer Model 42 2.1.2 Room Acoustic Rendering Equation 43 2.2 Deterministic Modeling of Specular Reflections and Diffractions 45 2.2.1 Image Source Method for a Single Surface 45 2.2.2 Exact Image Source Solution for Shoebox-Shaped Rooms 46 2.2.3 Image Source Method for Arbitrarily Shaped Rooms 48 2.2.3.1 General Algorithm 48 2.2.3.1.1 The Contribution by an Image Source 50 2.2.3.2 Algorithm with Diffraction 50 2.2.3.2.1 Contribution by a First-Order Diffraction ES 51 2.2.4 Beam Tracing 52 2.3 Statistical Modeling of Geometrical Acoustics 54 2.3.1 Ray Tracing 54 2.3.2 Radiance Exchange Methods 56 2.3.3 Diffusion Equation Method 56 References 57 Chapter 3 Acoustics in Long Rooms 60 Jian Kang 60 Introduction 60 3.1 Fundamentals of Acoustic Characteristics in Long Rooms 60 3.1.1 Ray Theory 61 3.1.2 Wave Theory 62 3.1.3 Definition of Long Rooms 62 3.2 Acoustic Simulation of Long Rooms 63 3.2.1 Image Source Model 64 3.2.2 Radiosity Model 67 3.2.3 Ray Tracing and Combined Ray Tracing and Radiosity 69 3.3 Acoustic Formulae for Long Rooms 69 3.3.1 SPL with Geometrically Reflecting Boundaries 69 3.3.2 T30 with Geometrically Reflecting Boundaries 71 3.3.3 SPL with Diffusely Reflecting Boundaries 72 3.3.4 SPL Based on Wave Theory 72 3.3.5 An Empirical SPL Formula 73 3.4 Effects of Designable Factors 73 3.4.1 Sound Distribution 73 3.4.2 Reverberation with a Single Source 75 3.4.3 Reverberation with Multiple Sources 78 3.5 Case Studies Based on Scale Modeling 81 3.5.1 Diffusers 81 3.5.2 Absorbers 83 3.5.3 Reflectors and Obstructions 84 3.5.4 Train Noise and the STI in Underground Stations 85 3.6 Case Studies Based on Site Measurements 85 Defining Terms 87 References 88 For Further Information 89 Chapter 4 Acoustics in Coupled Volume Systems 90 Ning Xiang 90 Abstract 90 4.1 Introduction 90 4.2 Statistical Acoustics Models 91 4.3 Wave-Acoustical Methods 93 4.4 Geometrical Acoustics Methods 95 4.5 Diffusion Equation Methods 96 4.6 Experimental Investigations and Analysis Tools 99 Summary 102 Acknowledgments 102 References 102 Chapter 5 Advanced Measurements Techniques: Methods in Architectural Acoustics 106 Wolfgang Ahnert and Stefan Feistel 106 5.1 Overview 106 5.2 Measurement Methods 107 5.2.1 Traditional Sound Level Measurements and Assessment 107 5.2.2 Measurement Techniques Based on Fourier Analysis 108 5.2.2.1 Fundamentals 108 5.2.2.2 Conventional Excitation Signals 110 5.2.2.3 Sweep-Based Measurements 112 5.2.2.4 Noise Applications 113 5.2.2.5 Technique Using Maximum-Length Sequences 114 5.2.2.6 Time-Delay Spectrometry Method 116 5.2.2.7 Measurements Using Arbitrary Excitation Signals 116 5.2.3 Absolute and Relative Measurements, Calibration 120 5.2.3.1 Measurement Parameters 120 5.2.4 Measurement Errors, Optimization, and Limits of Application 121 5.2.4.1 Measurement System and Measurement Chain 122 5.2.4.2 External Influences 122 5.2.4.3 Post-Processing 123 5.3 Room Acoustic Measurements 125 5.3.1 Introductory Comments 125 5.3.2 Selection of Measurement Locations 126 5.3.3 Measurement of Room Acoustic Properties 126 5.3.4 Time Domain Quantities 127 5.3.5 Frequency Domain Quantities 130 5.3.6 Time-Frequency Representation (Waterfall Plots) 130 5.3.7 Special Applications 130 5.3.7.1 Filtering and Averaging 131 5.3.7.2 In Situ Measurement of the Absorption Coefficient 133 5.3.7.3 Measurement of Scattering Coefficients 134 5.3.7.4 Modal Analysis 136 5.4 Applications in Sound Reinforcement 137 5.4.1 Electrical Verification 137 5.4.1.1 Subjective Tests 137 5.4.1.2 Electrical Measurements 138 5.4.2 Acoustic Measurement and Tuning 139 5.4.2.1 Introductory Comment 139 5.4.2.2 SPL Coverage 140 5.4.2.3 Maximum Sound Pressure Level 141 5.4.2.4 Measurement of the Frequency Response 142 5.4.2.5 Measurement of the Speech Intelligibility STI 143 5.4.2.6 Subjective Assessment of Speech Transmission Index Values 145 5.4.2.7 Signal Roughness and Source Mislocalization 145 5.4.2.8 Subjective Assessment 146 5.4.3 Additional Measurements 147 5.4.3.1 Signal Alignment 147 5.4.3.2 Feedback Test 147 5.4.3.3 Polarity Test 147 5.5 Final Remarks 148 References 148 Chapter 6 Room-Acoustic Energy Decay Analysis 150 Ning Xiang 150 Abstract 150 6.1 Introduction 150 6.2 Integrated Impulse-Response Method 151 6.2.1 Schroeder Integration and Energy-Time Function (Curve) 151 6.2.2 Schroeder Decay Model 153 6.2.3 Characteristics of Schroeder Decay Functions 155 6.3 Truncation Approach 155 6.4 Noise Subtraction 156 6.4.1 Pre-Subtraction 156 6.4.2 Post-Subtraction (Noise Compensation) 157 6.4.3 Least-Squares Fitting for Noise Estimation 158 6.5 Nonlinear Regression 159 6.6 Two Levels of Bayesian Decay Analysis 162 6.6.1 Model Selection: The Second Level of Inference 162 6.6.2 Parameter Estimation: The First Level of Inference 163 6.6.3 Bayesian Information Criterion 163 6.6.4 Advanced Sampling Methods 165 Summary 166 Acknowledgment 166 References 166 Chapter 7 Sound Insulation in Buildings 168 Carl Hopkins 168 7.1 Introduction 168 7.2 Airborne Sound Insulation—Direct Transmission 168 7.2.1 Descriptors 168 7.2.2 Solid Plates 169 7.2.3 Cavity Wall and Floor Constructions 173 7.2.4 Wall and Floor Linings 177 7.2.5 Air Paths Due to Holes, Gaps, and Slits 181 7.2.6 Glazing and Windows 181 7.2.7 Doors 183 7.2.8 Combining Sound Reduction Indices for Different Building Elements that Form a Single Surface 184 7.3 Impact Sound Insulation—Direct Transmission 184 7.3.1 Standard Impact Sources 185 7.3.2 Descriptors 188 7.3.3 Solid Plates 188 7.3.4 Timber Floor 188 7.3.5 Floor Coverings 189 7.4 Sound Insulation In Situ 191 7.4.1 Descriptors 191 7.4.1.1 Sound Insulation Within Buildings 191 7.4.1.2 Façade Sound Insulation 193 7.4.2 Flanking Transmission Between Rooms—Airborne Sound Insulation 194 7.4.3 Flanking Transmission Between Rooms—Impact Sound Insulation 199 Acknowledgments 200 References 201 Chapter 8 Auditory Perception in Rooms 204 Jonas Braasch and Jens Blauert 204 8.1 Introduction 204 8.2 Localization of a Single Sound Source 204 8.3 Listening to Multiple Sound Sources 209 8.3.1 The Precedence Effect 210 8.3.2 Spatial Impression 212 8.3.3 Instrumental Indices for Perceptual Assessment of Rooms 216 8.3.4 Limitations of the Room-Impulse-Response Concept 220 8.4 The Quality of the Acoustics 221 Conclusion 224 Acknowledgments 224 References 224 Chapter 9 Auralization 228 Michael Vorländer 228 9.1 Introduction 228 9.2 Definitions and Standards in Architectural Acoustics 229 9.2.1 Impulse Responses in Rooms 229 9.2.2 Sound Transmission Between Rooms 230 9.2.3 Structure-Borne Sound in Buildings 230 9.3 Audio Signal Processing for Architectural Acoustics 231 9.3.1 Discrete and Fast Fourier Transformation 232 9.3.2 Convolution 233 9.4 The Concept of Auralization 234 9.4.1 Source Characterization 236 9.4.2 Filter Construction 237 9.4.2.1 Filter Design from Room Impulse Response Data 237 9.4.2.2 Filter Design from Sound Transmission Data 240 9.4.2.3 Filter Design from Impact Sound Data 242 9.4.3 Spatial Sound Reproduction 243 9.5 Challenges and Limitations 244 9.5.1 Level of Detail of the Room Model 245 9.5.2 Diffraction and Seat-Dip Effect 245 9.5.3 Uncertain Absorption 246 9.5.4 Modes 246 9.6 Real-Time Processing for Virtual Room Acoustics 246 Defining Terms 247 References 249 For Further Information 250 Chapter 10 Room-Related Sound Representation Using Loudspeakers 252 Jens Blauert and Rudolf Rabenstein 252 10.1 Introduction 252 10.2 Intensity Stereophony 253 10.3 Amplitude-Difference Panning 255 10.4 Surround 258 10.5 Spherical-Harmonics Synthesis 259 10.5.1 Classical Ambisonics 259 10.5.2 Higher-Order Ambisonics 261 10.6 Wave-Field Synthesis 264 10.7 Binaural-Cue Selection 266 10.8 Discussion and Conclusions 269 Final Remarks 271 Acknowledgments 271 References 271 Chapter 11 Environmental Acoustics 274 Jian 274 Introduction 274 11.1 Environmental Sound Propagation and Noise Mapping 274 11.1.1 Source Model 274 11.1.2 Geometrical Divergence with Point, Line, and Plane Sources 275 11.1.3 Ground Attenuation 275 11.1.4 Atmospheric Absorption 276 11.1.5 Vegetation 276 11.1.6 Noise Barriers: Basic Configurations 276 11.1.7 Noise Barriers: Strategic Design 277 11.1.8 Noise Mapping 279 11.2 Micro-Scale Sound Propagation 279 11.2.1 Image Source Method 280 11.2.2 Ray-Tracing 280 11.2.3 Radiosity Model 281 11.2.4 Transport Theory 283 11.2.5 Wave-Based Models 283 11.2.6 Empirical Formulae 284 11.2.7 Meso-Scale Models 284 11.2.8 Auralization 284 11.2.9 Physical Scale Modeling 285 11.2.10Noise Control in Street Canyons 285 11.2.11Noise Control in Urban Squares 287 11.2.12Vegetation in Urban Context 288 11.3 Environmental Noise Indicators and Standards 288 11.3.1 Indicators 288 11.3.2 Standards and Regulations 289 11.4 Noise Perception 290 11.5 Urban Soundscape 291 11.5.1 Sound 292 11.5.2 Space 293 11.5.3 People 293 11.5.4 Environment 295 11.5.5 A Framework for Soundscape Description 295 For Further Information 296 References 296 Part II: Architectural Acoustics Practice 300 Chapter 12 Sound System Design and Room Acoustics 300 Wolfgang 300 12.1 Basics in Room Acoustics 301 12.1.1 Subjective Assessment of the Quality of Sound Events 301 12.1.2 Acoustic and Sound System Design Criteria and Quality Parameters in Rooms 302 12.1.2.1 Reverberation Time 302 12.1.2.2 Energy Criteria 306 12.1.2.2.1 Principal Measures for Speech Transmission 308 12.1.2.2.2 Measures for Music Reproduction 314 12.1.2.2.3 Measures for Music and Speech Reproduction and Binaural Measures 315 12.1.3 Basics in Sound Propagation for Sound System Design in Open Spaces 320 12.1.3.1 Auditory Localization 325 12.1.3.2 Effect of High Loudness Levels on the Auditory System 326 12.1.3.2.1 Mechanism of Hearing Impairment 326 12.1.3.2.2 Causes for High Sound Levels in Sound Reinforcement Systems 327 12.1.3.2.3 Possibilities for Reducing Excessive Sound Levels 327 12.2 Limits of Sound Systems in Rooms 328 12.2.1 Level Restrictions 328 12.2.2 Primary and Secondary Structures of Spaces and Noise Floor Considerations 329 12.2.3 Mono or Multipurpose Spaces 332 12.3 How to Design a Sound System 334 12.3.1 Introduction 334 12.3.2 Acoustic Sources and Loudspeaker Systems 334 12.3.2.1 Point Sources 334 12.3.2.2 Sound Columns 340 12.3.2.3 Line Arrays 342 12.3.2.4 Digitally Controlled Line Arrays 343 12.3.3 Receivers and Microphone Systems 344 12.3.3.1 Acoustic Evaluation with Human Ears 344 12.3.3.2 Microphones 344 12.3.3.2.1 Sensitivity 345 12.3.3.2.2 Directivity Behavior 345 12.3.4 Sound Processing Equipment 346 12.3.4.1 Delay Equipment 346 12.3.4.2 Effect Devices 347 12.3.4.3 Reverberation Equipment 347 12.3.4.4 Feedback Suppressor 349 12.3.4.4.1 Use of Narrow Band Filters 349 12.3.4.4.2 Frequency Shifter 350 12.3.4.5 Filters 350 12.4 Calculation of Sound Reinforcement Systems 352 12.4.1 Analytic Sound Level Calculation 353 12.4.1.1 Free Field (Direct Field of the Loudspeaker) 353 12.4.1.2 Diffuse Field 353 12.4.1.3 Real Rooms 354 12.4.1.4 Conclusions for the Practice 354 12.4.2 Basic Tools and Parameters for Computer-Based Calculations 355 12.4.2.1 Computer Models 355 12.4.2.1.1 Wall Materials 355 12.4.2.1.2 Transducer Data for Acoustic Simulation 359 12.5 Computer-Based Calculation of Sound Level and Other Parameters 365 12.5.1 Room Acoustic Simulation 365 12.5.1.1 Statistical Approach 365 12.5.1.1.1 Reverberation Time 365 12.5.1.1.2 Objective Room Acoustic Measures 366 12.5.1.2 Ray-Tracing Approach 366 12.5.1.3 Results of All of These Calculations 367 12.5.2 Sound System Design 368 12.5.2.1 Aiming 368 12.5.2.2 Time-Arrivals, Delay, and Alignment 369 12.5.2.3 SPL Calculations 373 12.5.2.4 Mapping, Single-Point Investigations 374 12.5.3 Auralization 377 12.5.3.1 Useful Application of Auralization 377 12.5.3.2 Limits and Abuse of Auralization 378 Summary 378 References 378 Chapter 13 Noise Control in Heating, Ventilation, and Air Conditioning Systems 382 Douglas 382 13.1 Noise Criteria 382 13.2 Duct-Borne Noise Transmission 383 13.2.1 Sound Attenuation in Straight Ducts 384 13.2.2 Sound Attenuation by Duct Divisions 385 13.2.3 Sound Attenuation by Duct Cross Section Area Changes 385 13.2.4 Sound Attenuation by Elbows 385 13.2.5 Prefabricated Silencers 386 13.2.6 Sound Attenuation by Plenums 387 13.2.7 Room Effect 388 13.3 Flow Noise in Ducted Systems 388 13.3.1 Main Duct System Design 388 13.3.2 Diffuser and Grille Selection 390 13.4 Noise Break-Out/Break-In 390 13.5 Fans 391 13.6 Terminal Boxes/Valves 392 13.7 Vibration Isolation Considerations for Building Mechanical Systems 393 13.8 Outdoor Noise Emissions 395 References 396 Chapter 14 Acoustical Design of Worship Spaces 398 Ewart A 398 14.1 Introduction 398 14.2 Fundamentals and Principles 399 14.2.1 Requirements for Good Hearing 399 14.2.1.1 Quiet Background 399 14.2.1.2 Adequate Loudness 399 14.2.1.3 Suitable Reverberation 399 14.2.1.4 Good Distribution of Sound 400 14.2.2 Sound Propagation Outdoors 400 14.2.3 Sound Distribution in a Room 401 14.2.3.1 Acoustical Properties of Materials 401 14.2.3.2 Sound Transmission Loss 402 14.2.4 Planning for a New Building 402 14.2.5 Selection of Acoustical Criteria 403 14.2.5.1 Use of Octave-Band Analysis 403 14.2.5.2 Criteria for Background Noise 403 14.2.5.3 Criteria for Reverberation 405 14.2.6 Control of Outdoor Noise 405 14.2.6.1 Site Evaluation 405 14.2.6.2 Outdoor Noise Level Minus Indoor Level Is Required Minimum Noise Reduction 406 14.2.6.3 Outdoor Equipment Noise 406 14.2.6.4 Noise Created by Building Enclosure 406 14.2.7 Control of Indoor Noise 406 14.2.7.1 Noise Control Between Spaces 406 14.2.7.2 Limitations of Divisible Spaces 408 14.2.7.3 Control of Vibration and Structure-Borne Noise 408 14.2.7.4 Impact Noise Control 408 14.2.8 Ventilation and Air Conditioning Noise Control 408 14.2.8.1 Control of Equipment Noise 408 14.2.8.2 Control of Fan Noise in Ductwork 408 14.2.8.3 Air Distribution—Supply and Return 409 14.2.8.4 Nonducted Air Return 410 14.2.9 Other Equipment Noise 410 14.2.10 Acoustics of Sanctuary 410 14.2.10.1 Background Noise Level 410 14.2.10.2 Size and Shape of Space 410 14.2.10.3 Sound Reflecting and Absorbing Materials 411 14.2.10.4 Reverberation Time 411 14.2.10.5 Requirements for Speech 412 14.2.10.6 Requirements for Music 412 14.2.10.7 Choir Rehearsal Room 412 14.2.10.8 Accommodating Nonworship Events 412 14.3 Applications to Design and Construction 413 14.3.1 Transition from Design to Construction 413 14.3.2 Site Noise Control 413 14.3.2.1 Site Noise Measurements 413 14.3.2.2 Building Enclosure 414 14.3.2.3 Outdoor Air Conditioning Equipment 414 14.3.3 Control of Indoor Noise 416 14.3.3.1 Noise Isolation Between Spaces 416 14.3.3.2 Movable Partition Details 416 14.3.3.3 Impact Noise Control 416 14.3.3.4 Ventilation and Air Conditioning Noise Control 417 14.3.3.5 Air Distribution Noise Control 417 14.3.4 Acoustics of Sanctuary 419 14.3.4.1 Size and Shape of Sanctuary 419 14.3.4.2 Organ and Choir 420 14.3.4.3 Related Design Requirements 421 14.3.4.4 Sound Reflecting and Absorbing Materials 421 14.3.4.5 Reverberation Time 422 14.3.4.6 Estimation of Reverberation Time 423 14.3.4.7 Choir Rehearsal Room 424 14.3.4.8 Sound Amplification 425 14.3.4.9 Adapting for Other Events 425 14.3.5 Remodeling of Existing Facilities 426 14.3.6 Getting Things Built Properly 427 14.3.6.1 Contractual Arrangements 427 14.3.6.2 Importance of Details 427 14.3.6.3 Ambiguities in Terminology 427 14.3.6.4 Value Engineering 428 14.3.6.5 Design Build 428 14.3.6.6 Bidding Period 428 14.3.6.7 Monitoring Construction 428 14.3.6.8 Acceptance Testing of Facilities 429 Summary 429 Acknowledgements 430 References 430 Further Reading 430 Appendix—Defining Terms 430 Chapter 15 Performing Arts Spaces 432 Ronald L. McKay, David Conant, and K. Anthony Hoover 432 Prologue 432 A. Types of Spaces 432 B. Chapter Sections 432 C. Obtaining Desired Results 433 Chapter 15 Unit I Music Performance Spaces 434 Ronald L 434 15.I.1 Introduction 434 15.I.2 Basics for All Music Performance Halls 434 15.I.2.1 Design and Construction Processes 434 15.I.2.2 Background Noise 435 15.I.2.3 Seating Capacities 435 15.I.2.4 Reverberation and Reverberation Times 436 15.I.2.5 Hall Volume 440 15.I.2.6 Hall Finish Materials 441 15.I.2.6.1 Floors and Chairs 441 15.I.2.6.2 Walls, Balcony Faces, Ceilings, and Soffits 442 15.I.2.7 Basic Hall Shaping 444 15.I.2.7.1 What Not to Do 444 15.I.2.7.2 Appropriate and Uniform Loudness 444 15.I.2.7.3 Sound Arrival Times at Audience Members and Performers 446 15.I.2.7.4 Lateral Sound Reflections to the Audience 448 15.I.2.8 Platform and Stage Planning 450 15.I.2.9 Audience Seating Configurations 454 15.I.2.10 Clouds and Canopies 456 15.I.2.11 Detailed Surface Shaping 459 15.I.3 Design Highlights: Concert, Recital, and Pipe Organ Halls 461 15.I.3.1 Introduction 461 15.I.3.2 Platform Designs 461 15.I.3.2.1 Concert Halls 461 15.I.3.2.2 Recital Halls 461 15.I.3.2.3 Concert Pipe Organ Halls 461 15.I.3.3 Hall Shaping and Materials 464 15.I.3.4 Examples 464 15.I.4 Design Highlights: Multipurpose Halls with Variable Acoustics 468 15.I.4.1 Introduction 468 15.I.4.2 The Problems 468 15.I.4.3 The Solutions and Key Details for a Concert Hall 470 15.I.4.4 The Solutions and Key Details for a Multipurpose Hall 471 15.I.4.5 Examples 472 15.I.5 Design Highlights: Opera Houses 476 15.I.5.1 Introduction 476 15.I.5.3.1 Seating Capacity/House Size 477 15.I.5.3.3 Basic Hall Shaping and Materials 479 15.I.5.3.2 Proscenium Size and Form 477 15.I.5.2 Stage and Orchestra Pit Design 477 15.I.5.3 Hall Shaping and Materials 477 15.I.5.4 Examples 482 15.I.6 Design Highlight: Halls for World, Country, Jazz, and Popular Music 482 15.I.6.1 Introduction 482 15.I.6.2 Basic Concepts 482 15.I.6.3 Author’s Assorted Impressions 485 15.I.6.3.1 Broadway-Style Theaters 485 15.I.6.3.2 Fortunate Halls 485 15.I.6.3.3 Las Vegas-Style Showrooms 485 15.I.6.3.4 Jazz Venues and Nightclubs 486 15.I.6.3.5 Ballrooms and Dance Halls 486 15.I.8 Further Reading 486 15.I.8.1 Books 486 15.I.8.2 Papers in Technical Journals 487 Chapter 15 Unit II Dramatic Arts Spaces 488 David A 488 15.II.1 Introduction 488 15.II.2 What You Need to Know: Broad Design Principles 489 15.II.2.1 Source → Path → Receiver 489 15.II.2.1.1 Source 489 15.II.2.1.2 Travel Path(s) 489 15.II.2.1.3 Receiver 490 15.II.2.2 Speech Intelligibility Descriptors 490 15.II.2.3 Aberrant Reflections 490 15.II.2.4 Guideline for Assessing and Designing for Individual Reflection Strength 491 15.II.3 Three Basic Theater Forms 491 15.II.3.1 The Proscenium Theater 495 15.II.3.1.1 Characteristic Elements 495 15.II.3.1.1.1 The Proscenium Opening 495 15.II.3.1.1.2 Catwalks and Tension Grids 497 15.II.3.1.1.3 Seating Above Orchestra Level 498 15.II.3.1.1.4 Orchestra Pit 498 15.II.3.1.2 Design Principles for Proscenium Theaters 499 15.II.3.1.2.1 General Design Guidelines 499 15.II.3.1.3 Example: South Mountain Community College Theater 502 15.II.3.2 Thrust Stage Theater Design 504 15.II.3.2.1 Characteristic Elements 504 15.II.3.2.1.1 Stage Sets and Orchestra Pits 504 15.II.3.2.1.2 Catwalks and Tension Grids 504 15.II.3.2.2 Design Principles for Thrust Stage Theaters 505 15.II.3.2.2.1 General Design Guidelines 505 15.II.3.2.3 Example: Bistline Theater at Idaho State University 507 15.II.3.2.3.1 Design Attributes and Features 507 15.II.3.3 Experimental Theaters 509 15.II.3.3.1 Characteristic Elements 509 15.II.3.3.2 Design Principles for Experimental Theaters 509 15.II.3.3.2.1 General Design Guidelines 509 15.II.3.3.3 Example: South Mountain Community College Studio Theater 512 15.II.3.3.3.1 Design Attributes 512 15.II.3.3.3.2 Design Features 513 15.II.4 Considerations for Opera and Musical Theater (Addressing Pits and Eyebrows) 513 15.II.4.1 Issues of Balance and Communications of Stage Voices with Pit Musicians 513 15.II.4.1.1 The Pit Design 514 15.II.4.1.2 The Eyebrow Design 514 15.II.5 Considerations Unique to Nonprofessional Venues (Addressing the Nonprofessional Vocal Effort in Training As Well As Professional Voices) 515 15.II.5.1 Acoustical Criteria 515 15.II.5.2 Value Extraction Considerations 516 15.II.5.3 Specific Additional Design Guidance 516 15.II.5.3.1 Construction and Finish Materials 516 15.II.5.3.2 Variable Acoustics 516 15.II.5.3.3 Control Room 517 15.II.5.3.4 More Audio 517 References 518 Further Reading 518 Chapter 15 Unit III Music Education Spaces 520 K. Anthony 520 15.III.1 Introduction 520 15.III.2 General Isolation Concerns 521 15.III.3 General Mechanical System Noise and Vibration Concerns 522 15.III.4 General Surface Treatments and Shaping Concerns 525 15.III.5 Electroacoustics 526 15.III.6 Acoustical Criteria 526 15.III.6.1 Sound Isolation: Sound Transmission Class (STC) 526 15.III.6.2 HVAC Noise: NC (Noise Criteria) 527 15.III.6.3 Surface Treatments: NRC (Noise Reduction Coefficient) 527 15.III.7 Types of Spaces 528 15.III.7.1 Classrooms 528 15.III.7.2 Faculty Offices 529 15.III.7.3 Practice Rooms 530 15.III.7.4 Ensemble Rooms 532 15.III.7.5 Large Rehearsal Rooms 533 15.III.7.6 Critical Listening Rooms 535 15.III.7.7 Recording Studios 536 15.III.7.8 World Music Rooms 538 15.III.7.9 Libraries 539 15.III.7.10 Lobbies/Atriums 539 Common Ground for Discussion 540 Further Reading 540 Glossary 542 Front Cover......Page 1 Title Page......Page 2 Copyright......Page 3 Contents......Page 6 Preface......Page 20 About the Editor......Page 22 About the Contributors......Page 24 1.1 Room Acoustic Modeling......Page 32 1.2 Analytical Solutions......Page 33 1.2.2 Modal Solution + Propagating Waves......Page 35 1.2.3 Domain Matching......Page 36 1.3.1 Finite Difference Methods......Page 37 References......Page 39 2.1.1 Acoustic Radiative Transfer Model......Page 42 2.1.2 Room Acoustic Rendering Equation......Page 43 2.2.1 Image Source Method for a Single Surface......Page 45 2.2.2 Exact Image Source Solution for Shoebox-Shaped Rooms......Page 46 2.2.3.1 General Algorithm......Page 48 2.2.3.2 Algorithm with Diffraction......Page 50 2.2.3.2.1 Contribution by a First-Order Diffraction ES......Page 51 2.2.4 Beam Tracing......Page 52 2.3.1 Ray Tracing......Page 54 2.3.3 Diffusion Equation Method......Page 56 References......Page 57 3.1 Fundamentals of Acoustic Characteristics in Long Rooms......Page 60 3.1.1 Ray Theory......Page 61 3.1.3 Definition of Long Rooms......Page 62 3.2 Acoustic Simulation of Long Rooms......Page 63 3.2.1 Image Source Model......Page 64 3.2.2 Radiosity Model......Page 67 3.3.1 SPL with Geometrically Reflecting Boundaries......Page 69 3.3.2 T30 with Geometrically Reflecting Boundaries......Page 71 3.3.4 SPL Based on Wave Theory......Page 72 3.4.1 Sound Distribution......Page 73 3.4.2 Reverberation with a Single Source......Page 75 3.4.3 Reverberation with Multiple Sources......Page 78 3.5.1 Diffusers......Page 81 3.5.2 Absorbers......Page 83 3.5.3 Reflectors and Obstructions......Page 84 3.6 Case Studies Based on Site Measurements......Page 85 Defining Terms......Page 87 References......Page 88 For Further Information......Page 89 4.1 Introduction......Page 90 4.2 Statistical Acoustics Models......Page 91 4.3 Wave-Acoustical Methods......Page 93 4.4 Geometrical Acoustics Methods......Page 95 4.5 Diffusion Equation Methods......Page 96 4.6 Experimental Investigations and Analysis Tools......Page 99 References......Page 102 5.1 Overview......Page 106 5.2.1 Traditional Sound Level Measurements and Assessment......Page 107 5.2.2.1 Fundamentals......Page 108 5.2.2.2 Conventional Excitation Signals......Page 110 5.2.2.3 Sweep-Based Measurements......Page 112 5.2.2.4 Noise Applications......Page 113 5.2.2.5 Technique Using Maximum-Length Sequences......Page 114 5.2.2.7 Measurements Using Arbitrary Excitation Signals......Page 116 5.2.3.1 Measurement Parameters......Page 120 5.2.4 Measurement Errors, Optimization, and Limits of Application......Page 121 5.2.4.2 External Influences......Page 122 5.2.4.3 Post-Processing......Page 123 5.3.1 Introductory Comments......Page 125 5.3.3 Measurement of Room Acoustic Properties......Page 126 5.3.4 Time Domain Quantities......Page 127 5.3.7 Special Applications......Page 130 5.3.7.1 Filtering and Averaging......Page 131 5.3.7.2 In Situ Measurement of the Absorption Coefficient......Page 133 5.3.7.3 Measurement of Scattering Coefficients......Page 134 5.3.7.4 Modal Analysis......Page 136 5.4.1.1 Subjective Tests......Page 137 5.4.1.2 Electrical Measurements......Page 138 5.4.2.1 Introductory Comment......Page 139 5.4.2.2 SPL Coverage......Page 140 5.4.2.3 Maximum Sound Pressure Level......Page 141 5.4.2.4 Measurement of the Frequency Response......Page 142 5.4.2.5 Measurement of the Speech Intelligibility STI......Page 143 5.4.2.7 Signal Roughness and Source Mislocalization......Page 145 5.4.2.8 Subjective Assessment......Page 146 5.4.3.3 Polarity Test......Page 147 References......Page 148 6.1 Introduction......Page 150 6.2.1 Schroeder Integration and Energy-Time Function (Curve)......Page 151 6.2.2 Schroeder Decay Model......Page 153 6.3 Truncation Approach......Page 155 6.4.1 Pre-Subtraction......Page 156 6.4.2 Post-Subtraction (Noise Compensation)......Page 157 6.4.3 Least-Squares Fitting for Noise Estimation......Page 158 6.5 Nonlinear Regression......Page 159 6.6.1 Model Selection: The Second Level of Inference......Page 162 6.6.3 Bayesian Information Criterion......Page 163 6.6.4 Advanced Sampling Methods......Page 165 References......Page 166 7.2.1 Descriptors......Page 168 7.2.2 Solid Plates......Page 169 7.2.3 Cavity Wall and Floor Constructions......Page 173 7.2.4 Wall and Floor Linings......Page 177 7.2.6 Glazing and Windows......Page 181 7.2.7 Doors......Page 183 7.3 Impact Sound Insulation—Direct Transmission......Page 184 7.3.1 Standard Impact Sources......Page 185 7.3.4 Timber Floor......Page 188 7.3.5 Floor Coverings......Page 189 7.4.1.1 Sound Insulation Within Buildings......Page 191 7.4.1.2 Façade Sound Insulation......Page 193 7.4.2 Flanking Transmission Between Rooms—Airborne Sound Insulation......Page 194 7.4.3 Flanking Transmission Between Rooms—Impact Sound Insulation......Page 199 Acknowledgments......Page 200 References......Page 201 8.2 Localization of a Single Sound Source......Page 204 8.3 Listening to Multiple Sound Sources......Page 209 8.3.1 The Precedence Effect......Page 210 8.3.2 Spatial Impression......Page 212 8.3.3 Instrumental Indices for Perceptual Assessment of Rooms......Page 216 8.3.4 Limitations of the Room-Impulse-Response Concept......Page 220 8.4 The Quality of the Acoustics......Page 221 References......Page 224 9.1 Introduction......Page 228 9.2.1 Impulse Responses in Rooms......Page 229 9.2.3 Structure-Borne Sound in Buildings......Page 230 9.3 Audio Signal Processing for Architectural Acoustics......Page 231 9.3.1 Discrete and Fast Fourier Transformation......Page 232 9.3.2 Convolution......Page 233 9.4 The Concept of Auralization......Page 234 9.4.1 Source Characterization......Page 236 9.4.2.1 Filter Design from Room Impulse Response Data......Page 237 9.4.2.2 Filter Design from Sound Transmission Data......Page 240 9.4.2.3 Filter Design from Impact Sound Data......Page 242 9.4.3 Spatial Sound Reproduction......Page 243 9.5 Challenges and Limitations......Page 244 9.5.2 Diffraction and Seat-Dip Effect......Page 245 9.6 Real-Time Processing for Virtual Room Acoustics......Page 246 Defining Terms......Page 247 References......Page 249 For Further Information......Page 250 10.1 Introduction......Page 252 10.2 Intensity Stereophony......Page 253 10.3 Amplitude-Difference Panning......Page 255 10.4 Surround......Page 258 10.5.1 Classical Ambisonics......Page 259 10.5.2 Higher-Order Ambisonics......Page 261 10.6 Wave-Field Synthesis......Page 264 10.7 Binaural-Cue Selection......Page 266 10.8 Discussion and Conclusions......Page 269 References......Page 271 11.1.1 Source Model......Page 274 11.1.3 Ground Attenuation......Page 275 11.1.6 Noise Barriers: Basic Configurations......Page 276 11.1.7 Noise Barriers: Strategic Design......Page 277 11.2 Micro-Scale Sound Propagation......Page 279 11.2.2 Ray-Tracing......Page 280 11.2.3 Radiosity Model......Page 281 11.2.5 Wave-Based Models......Page 283 11.2.8 Auralization......Page 284 11.2.10Noise Control in Street Canyons......Page 285 11.2.11Noise Control in Urban Squares......Page 287 11.3.1 Indicators......Page 288 11.3.2 Standards and Regulations......Page 289 11.4 Noise Perception......Page 290 11.5 Urban Soundscape......Page 291 11.5.1 Sound......Page 292 11.5.3 People......Page 293 11.5.5 A Framework for Soundscape Description......Page 295 References......Page 296 Wolfgang......Page 300 12.1.1 Subjective Assessment of the Quality of Sound Events......Page 301 12.1.2.1 Reverberation Time......Page 302 12.1.2.2 Energy Criteria......Page 306 12.1.2.2.1 Principal Measures for Speech Transmission......Page 308 12.1.2.2.2 Measures for Music Reproduction......Page 314 12.1.2.2.3 Measures for Music and Speech Reproduction and Binaural Measures......Page 315 12.1.3 Basics in Sound Propagation for Sound System Design in Open Spaces......Page 320 12.1.3.1 Auditory Localization......Page 325 12.1.3.2.1 Mechanism of Hearing Impairment......Page 326 12.1.3.2.3 Possibilities for Reducing Excessive Sound Levels......Page 327 12.2.1 Level Restrictions......Page 328 12.2.2 Primary and Secondary Structures of Spaces and Noise Floor Considerations......Page 329 12.2.3 Mono or Multipurpose Spaces......Page 332 12.3.2.1 Point Sources......Page 334 12.3.2.2 Sound Columns......Page 340 12.3.2.3 Line Arrays......Page 342 12.3.2.4 Digitally Controlled Line Arrays......Page 343 12.3.3.2 Microphones......Page 344 12.3.3.2.2 Directivity Behavior......Page 345 12.3.4.1 Delay Equipment......Page 346 12.3.4.3 Reverberation Equipment......Page 347 12.3.4.4.1 Use of Narrow Band Filters......Page 349 12.3.4.5 Filters......Page 350 12.4 Calculation of Sound Reinforcement Systems......Page 352 12.4.1.2 Diffuse Field......Page 353 12.4.1.4 Conclusions for the Practice......Page 354 12.4.2.1.1 Wall Materials......Page 355 12.4.2.1.2 Transducer Data for Acoustic Simulation......Page 359 12.5.1.1.1 Reverberation Time......Page 365 12.5.1.2 Ray-Tracing Approach......Page 366 12.5.1.3 Results of All of These Calculations......Page 367 12.5.2.1 Aiming......Page 368 12.5.2.2 Time-Arrivals, Delay, and Alignment......Page 369 12.5.2.3 SPL Calculations......Page 373 12.5.2.4 Mapping, Single-Point Investigations......Page 374 12.5.3.1 Useful Application of Auralization......Page 377 References......Page 378 13.1 Noise Criteria......Page 382 13.2 Duct-Borne Noise Transmission......Page 383 13.2.1 Sound Attenuation in Straight Ducts......Page 384 13.2.4 Sound Attenuation by Elbows......Page 385 13.2.5 Prefabricated Silencers......Page 386 13.2.6 Sound Attenuation by Plenums......Page 387 13.3.1 Main Duct System Design......Page 388 13.4 Noise Break-Out/Break-In......Page 390 13.5 Fans......Page 391 13.6 Terminal Boxes/Valves......Page 392 13.7 Vibration Isolation Considerations for Building Mechanical Systems......Page 393 13.8 Outdoor Noise Emissions......Page 395 References......Page 396 14.1 Introduction......Page 398 14.2.1.3 Suitable Reverberation......Page 399 14.2.2 Sound Propagation Outdoors......Page 400 14.2.3.1 Acoustical Properties of Materials......Page 401 14.2.4 Planning for a New Building......Page 402 14.2.5.2 Criteria for Background Noise......Page 403 14.2.6.1 Site Evaluation......Page 405 14.2.7.1 Noise Control Between Spaces......Page 406 14.2.8.2 Control of Fan Noise in Ductwork......Page 408 14.2.8.3 Air Distribution—Supply and Return......Page 409 14.2.10.2 Size and Shape of Space......Page 410 14.2.10.4 Reverberation Time......Page 411 14.2.10.8 Accommodating Nonworship Events......Page 412 14.3.2.1 Site Noise Measurements......Page 413 14.3.2.3 Outdoor Air Conditioning Equipment......Page 414 14.3.3.3 Impact Noise Control......Page 416 14.3.3.5 Air Distribution Noise Control......Page 417 14.3.4.1 Size and Shape of Sanctuary......Page 419 14.3.4.2 Organ and Choir......Page 420 14.3.4.4 Sound Reflecting and Absorbing Materials......Page 421 14.3.4.5 Reverberation Time......Page 422 14.3.4.6 Estimation of Reverberation Time......Page 423 14.3.4.7 Choir Rehearsal Room......Page 424 14.3.4.9 Adapting for Other Events......Page 425 14.3.5 Remodeling of Existing Facilities......Page 426 14.3.6.3 Ambiguities in Terminology......Page 427 14.3.6.7 Monitoring Construction......Page 428 Summary......Page 429 Appendix—Defining Terms......Page 430 B. Chapter Sections......Page 432 C. Obtaining Desired Results......Page 433 15.I.2.1 Design and Construction Processes......Page 434 15.I.2.3 Seating Capacities......Page 435 15.I.2.4 Reverberation and Reverberation Times......Page 436 15.I.2.5 Hall Volume......Page 440 15.I.2.6.1 Floors and Chairs......Page 441 15.I.2.6.2 Walls, Balcony Faces, Ceilings, and Soffits......Page 442 15.I.2.7.2 Appropriate and Uniform Loudness......Page 444 15.I.2.7.3 Sound Arrival Times at Audience Members and Performers......Page 446 15.I.2.7.4 Lateral Sound Reflections to the Audience......Page 448 15.I.2.8 Platform and Stage Planning......Page 450 15.I.2.9 Audience Seating Configurations......Page 454 15.I.2.10 Clouds and Canopies......Page 456 15.I.2.11 Detailed Surface Shaping......Page 459 15.I.3.2.3 Concert Pipe Organ Halls......Page 461 15.I.3.4 Examples......Page 464 15.I.4.2 The Problems......Page 468 15.I.4.3 The Solutions and Key Details for a Concert Hall......Page 470 15.I.4.4 The Solutions and Key Details for a Multipurpose Hall......Page 471 15.I.4.5 Examples......Page 472 15.I.5.1 Introduction......Page 476 15.I.5.3 Hall Shaping and Materials......Page 477 15.I.5.3.3 Basic Hall Shaping and Materials......Page 479 15.I.6.2 Basic Concepts......Page 482 15.I.6.3.3 Las Vegas-Style Showrooms......Page 485 15.I.8.1 Books......Page 486 15.I.8.2 Papers in Technical Journals......Page 487 15.II.1 Introduction......Page 488 15.II.2.1.2 Travel Path(s)......Page 489 15.II.2.3 Aberrant Reflections......Page 490 15.II.3 Three Basic Theater Forms......Page 491 15.II.3.1.1.1 The Proscenium Opening......Page 495 15.II.3.1.1.2 Catwalks and Tension Grids......Page 497 15.II.3.1.1.4 Orchestra Pit......Page 498 15.II.3.1.2.1 General Design Guidelines......Page 499 15.II.3.1.3 Example: South Mountain Community College Theater......Page 502 15.II.3.2.1.2 Catwalks and Tension Grids......Page 504 15.II.3.2.2.1 General Design Guidelines......Page 505 15.II.3.2.3.1 Design Attributes and Features......Page 507 15.II.3.3.2.1 General Design Guidelines......Page 509 15.II.3.3.3.1 Design Attributes......Page 512 15.II.4.1 Issues of Balance and Communications of Stage Voices with Pit Musicians......Page 513 15.II.4.1.2 The Eyebrow Design......Page 514 15.II.5.1 Acoustical Criteria......Page 515 15.II.5.3.2 Variable Acoustics......Page 516 15.II.5.3.4 More Audio......Page 517 Further Reading......Page 518 15.III.1 Introduction......Page 520 15.III.2 General Isolation Concerns......Page 521 15.III.3 General Mechanical System Noise and Vibration Concerns......Page 522 15.III.4 General Surface Treatments and Shaping Concerns......Page 525 15.III.6.1 Sound Isolation: Sound Transmission Class (STC)......Page 526 15.III.6.3 Surface Treatments: NRC (Noise Reduction Coefficient)......Page 527 15.III.7.1 Classrooms......Page 528 15.III.7.2 Faculty Offices......Page 529 15.III.7.3 Practice Rooms......Page 530 15.III.7.4 Ensemble Rooms......Page 532 15.III.7.5 Large Rehearsal Rooms......Page 533 15.III.7.6 Critical Listening Rooms......Page 535 15.III.7.7 Recording Studios......Page 536 15.III.7.8 World Music Rooms......Page 538 15.III.7.10 Lobbies/Atriums......Page 539 Further Reading......Page 540 Glossary......Page 542