Auditorium Acoustics and Architectural Design Second Edition Michael Barron. J ^A Spon Press an imprint of Taylor & Francis LONDON AND NEWYORK
Contents Preface Preface to the first edition Foreword ix xi xiii 1 Introduction 1 2 Sound and rooms 10 2.1 The essence ofsound waves 10 2.2 The nature of music and speech sounds 12 2.3 Sound propagation 15 2.4 Sound in rooms 17 2.5 Reflections and the ear 19 2.6 Sound propagation in detail 20 2.7 Acoustic defects 25 2.8 Reverberation time design 28 2.9 Sound level distribution 35 3 Acoustics for the symphony concert hall 38 3.1 Introduction 38 3.2 The subjective dimension 39 3.3 Objective descriptions 45 3.4 Size, volume and form 47 3.5 Early reflection design 49 3.6 The diffusion question 53 3.7 Balcony design 54 3.8 Design for the performers (written by A.-C. Gade) 56 3.9 Acoustic modelling 61 3.10 Objective characteristics 66 4 The development of the concert hall 75 4.1 Introduction 75 4.2 Early developments 76 4.3 The classical rectangular concert hall 79
vi Contents 4.4 The directed sound hall 91 4.5 The fan-shaped hall 95 4.6 The synthesis in British post-war halls 98 4.7 The diffuse solution 98 4.8 A subdivided acoustic space? 101 4.9 The terraced concert hall 106 4.10 The lateral directed reflection sequence hall 110 4.11 Concert hall design in the 980s 114 4.12 Return to precedents 121 5 British concert hails and conclusions for concert hall acoustics 128 5.1 Royal Albert Hall, London 130 5.2 Usher Hall, Edinburgh 138 5.3 Philharmonic Hall, Liverpool 144 5.4 Watford Colosseum 149 5.5 Royal Festival Hall, London 153 5.6 Colston Hall, Bristol 160 5.7 Free Trade Hall, Manchester 165 5.8 Fairfield Hall, Croydon 170 5.9 The Lighthouse Concert Hall, Poole 175 5.10 Barbican Concert Hall, Barbican Centre, London 180 5.11 St David's Hall, Cardiff 186 5.12 Royal Concert Hall, Nottingham 192 5.13 Glasgow Royal Concert Hall 198 5.14 Birmingham Symphony Hall 203 5.15 Bridgewater Hall, Manchester 210 5.16 Waterfront Hall, Belfast 215 5.17 Acoustical design of concert halls in subjective and objective terms 222 5.18 Solutions to the large concert hall problem 225 6 Chamber music and recital halls 230 6.1 Introduction 230 6.2 Reverberation time and loudness 231 6.3 Room form for chamber music 233 6.4 Wigmore Hall, London 239 6.5 Queen Elizabeth Hall, London 242 6.6 The Makings Concert Hall, Snape, Suffolk 247 6.7 Faculty of Music Auditorium, Cambridge 251 6.8 Conclusions 256 7 Acoustics for speech 258 7.1 The nature of speech 258 7.2 Speech in the open air 261 7.3 Speech in rooms 262 7.4 Is there an optimum profile for theatre design? 264
Contents vii 7.5 Design for speech in theatres 267 7.6 The early reflection ratio 270 7.7 Acoustic measurement of theatres 273 7.8 Prediction of reverberation time in theatres 274 8 Theatre acoustics 276 8.1 Classical Greek and Roman theatre 276 8.2 Elizabethan theatre in London 282 8.3 The development of the proscenium theatre 283 8.4 The acoustics of six proscenium theatres 288 8.5 The thrust-stage theatre 306 8.6 The open stage 316 8.7 Theatre in the round 323 8.8 Conclusions 329 9 Acoustics for opera 333 9.1 Introduction 333 9.2 The elements of opera house design 336 9.3 Stage and pit design 345 9.4 Opera house form and acoustics 349 9.5 Objective assessment of opera houses 359 9.6 British opera houses 361 9.7 Conclusion 380 10 Acoustics for multi-purpose use 385 10.1 Introduction 385 10.2 Variable acoustic elements 386 10.3 The totally variable acoustic space 392 10.4 Meeting the requirements of both speech and music 393 10.5 Variable acoustics through electronics 394 10.6 The multi-purpose auditorium with flytower 399 10.7 Conclusions 407 11 Multi-purpose halls in Britain 410 11.1 Wembley Conference Centre 410 11.2 Central Hall, University ofyork 416 11.3 Butterworth Hall, University of Warwick Arts Centre 420 11.4 Assembly Rooms, Derby 424 11.5 The Hexagon, Reading 429 11.6 Eden CourtTheatre, Inverness 432 11.7 Theatre Royal, Plymouth 436 11.8 Derngate Centre, Northampton 441 11.9 Conclusions 448
viii Contents 12 The art and science of acoustics 451 12.1 Precedence and scientific design 451 12.2 Speech and theatre design 452 12.3 The concert hall 453 12.4 The opera house 454 12.5 The multi-purpose hall 455 12.6 The future 455 Appendix A: Sound reflection and reverberation calculation 457 A.I Reflection from finite plane and curved surfaces 457 A.2 The Quadratic Residue Diffuser 458 A. 3 Calculation of reverberation time 459 Appendix B: Objective measures for music auditoria 461 B. I The impulse response and the new objective measures 461 B.2 Prediction of occupied reverberation time 463 B.3 Revised theory and correction of energy measures for reverberation time change 464 Appendix C: Further objective results in concert halls 467 C. I Objective results in two New Zealand concert halls 467 C. 2 Objective results in Segerstrom Hall, California 469 Appendix D: Objective measures for speech auditoria 471 D. I Objective measures of speech intelligibility 471 D.2 The criterion speech level for theatres 473 D.3 Revised theory of sound level for use with speech 474 Name index 476 Subject index 481