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Acoustics of Concert Halls and Rooms SOME BASICS OF ARCHITECTURAL ACOUSTICS. Auditorium Acoustics Handbook of Acoustics ,Chapter 23 Principles of Vibration and Sound , Chapter 11. Kimmel Center. p vs r. log p vs log r. SOUND FIELD. Free field. Reflections. Sound decay.
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Acoustics of Concert Halls and RoomsSOME BASICS OF ARCHITECTURAL ACOUSTICS Auditorium Acoustics Handbook of Acoustics,Chapter23 Principles of Vibration and Sound, Chapter 11 Kimmel Center
p vs r log p vs log r SOUND FIELD Free field Reflections
Sound decay Sound decay in a 400 m3 classroom Sound pressure level as a function of time for that room
GROWTH AND DECAY OF REVERBERANT SOUND RT = K (volume / area) RT = 0.161 V/A(V in m3; A in m2 ) If room dimensions are given in feet, the formula may be written: RT= 0.049 V/A (V in ft.3 ; A in ft.2 )
Decay of reverberant sound • and (b) are decay curves of sound pressure and sound • level in a room with uniform energy distribution • (c) shows different initial and final reverberation times • (d) shows peaks due to prominent standing waves or room • resonances
Desirable reverberation times for various sizes and functions Variation of reverberation time with frequency in good halls
Kimmel Center Auditorium
Important criteria for concert halls: • Spatial impression • Intimacy • Early decay time • Clarity • “Warmth”