Last year I volunteered to help out with the renovation of a building on campus. People assemble there for banquets and weddings. The operators of the space field regular complaints of excessive reverberance: for instance, at a banquet a dean is recognizing faculty who have won teaching awards and each syllable of the dean’s speech seems to linger in the air too long, interfering with the next syllable before it is uttered. How much extra sound absorbing material, in square feet, should be added to move this room to a (1000 Hz) reverberation time of 0.40 seconds for improved speech intelligibility?
I measured the existing reverberation time to be 0.73 seconds at 1000Hz
The sound absorption coefficient (SAC or ⍺) of the absorbing material they chose, measured at 1000Hz, is 0.95
I measured the total surface area of all the surfaces in the room to be 4,365 sf
I measured the total volume of the room to be 11,619 cu ft
Assume that the absorbing material will replace gypsum board; the GWB being replaced has a 1000Hz sound absorption coefficient (SAC or ⍺) of 0.04
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