Norris-Eyring reverberation formula

Norris-Eyring reverberation formula

[′när·əs ′ī·riŋ ri‚vər·bə′rā·shən ‚fȯr·myə·lə]
(acoustics)
The reverberation time of a chamber, in seconds, is equal to 0.05 times its volume, in cubic feet, divided by the product of its surface area, in square feet, and the negative of the natural logarithm of 1 minus the absorption coefficient averaged over the surface.