Sound produced within any enclosed space will continue to exist in that space for some amount of time after it is created, decaying away until it is inaudible. If this decay time, known as the room's reverberation time, is too long, sounds will linger within the space and begin to overlap with new sounds being made, creating an unintelligible cacophony.
Long reverberation time = Poor Intelligibility | ||
Short reverberation time = Good Intelligibility |
A sufficient amount of acoustic absorption is required at all audible frequencies of sound in order to keep the reverberation time in a room short enough to have good intelligibility. The measurement of the reverberation time in a room is often referred to as RT60. The desired RT60 at an frequency varies from room to room. All ASC acoustic treatments alter the RT60 of a room to some degree. Acoustic treatment is developed with desired RT60 levels in mind.