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Rehearsal rooms

What are the significant acoustic properties of a good rehearsal room?

Current view in akuTEK Research is that the following topics are strongly related: stage acoustics, rehearsal rooms, performer’s perception, perceived reverberation. Stage acoustics and rehearsal room acoustics are important in order to develop musicians, orchestras and provide for good playng conditions—to the benefit of the listeners—and must be supported by knowledge of performer’s perception in general, and perceived reverberance in particular.

Traditionally, rehearsal room acoustics is described by reverberation time.

Problem: For a violinist playing in a symphony orchestra rehearsing in a 35 square meter, 100 cubic meter rehearsal room, what is the adequate RT?

If  T is similar to the hall where the music is to be performed, e.g. T=2.0 s, the sound level /support level would be too high.

In a room with dimensions 5m*7m*3m and average absorption coefficient a=0.10, we predict (at 1m distance): T30=1.2s;  EDT=1.1s;  STearly=1dB;  STlate=-1dB.

If support is similar to support on the stage where the music is to be performed, e.g. STearly=-13dB, the RT will be very short.

In a room with dimensions 5m*7m*3m and average absorption coefficient a=0.5, we predict (at 1m distance): T30=0.2s;  EDT=0.15s;  STearly=-10dB;  STlate=-40dB.

EDT is assumed to describe perceived reverberance, but on a concert hall stage at 1m from the source, EDT is in the order of 0.1s, which usually would be regarded as inaudible reverberance.

It may seem impossible to achieve acoustical conditions in a rehearsal room similar  to those on stage in a large concert hall. Is it—and if so, what are the preferred acoustical properties?

You may judge for yourself in the reverberance sound demo.

Running Reverberation is assumed to be important to the musician in a rehearsal room. Can a short and loud reverberation tail be perceived equivalent to a long and weak one?  How loud is my reverberation? - D Griesinger asks.

Tilted walls, flutter-echo, energy modes and standing waves

How much should room surfaces deviate from parallel to avoid unwanted acoustic effects? Angles in the order of 6-12 degrees have been suggested, but is the answer always angle-dependant? What if there is very short distance between the pair of walls? Follow link to this prediction demo.

(To be continued)

Rehearsal room acoustics