because of differences in the acoustical setting. Since an enclosed room presents acoustical boundaries (walls, floors & ceilings), sound indoors exhibits quite complex behavior. Each time a sound wave strikes a boundary, part of the wave'senergy is reflected and part is absorbed (see diag. 1).
Reflection& absorption are dependent on the freauencv of the sound wave
'
and the angle at which it strikes the boundary.
orption - When designing your system, note that e and furniture absorb sound, while glass and tile
tsound. The percentage of energy that a boundary orbs is often expressed by an absorption coefficientof boundarv material, where an absorlstion coefficient of
Reverberation - Reverberation is the reflectedsound waves continuingto bounce between the boundaries,losing energy with each reflection.When sound strikes the reflec- tive boundaries of a room, after a time the room is filled with random reflectedsound waves. Music and speech become unintelligible(see diag. 3A). To minimize reverberation in a highly reverberant room, it is advisable to install more speakers, and play them at lower levels (see diag. 3B).
