Abbingdon Music Research LS-77 Appendix G - Acoustics Background Information, G.1 Acoustics

Appendix G - Acoustics Background Information

G.1 Acoustics

When we talk about making a room "sound right", we are probably dealing with room acoustics. As a science acoustics has been around for about a hundred years. Until then good acoustics happened by experiment, by experience, or simply by accident.

Today we know a lot about the parameters that influence the "sound" of a room. Talking about the listening room we know that basically this room should act as neutral as possible. But this is not always the case. Lets just take a short look on some of the issues that one must be aware of.

G.2 Good acoustics

Here is a list of important parameters concerning good acoustics.

yProper reverberation time

yGood sound distribution

yAdequate sound pressure level

yLow background noise level

yNo echo (flutter echo)

Now lets have a look on these headlines that will be adequate for the most purposes concerning sound production.

G.3 Reverberation time

The reverberation time is defined by the time it takes a sound to attenuate 60 dB after the source is stopped. In real life we can experience reverb times from approximately 0sec. (outdoors or in anechoic chambers) to something like 10-12 sec. In special reverb chambers the time may exceed 20 sec. Listening rooms normally should have a reverb time around 0.2 - 0.3 sec.

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