Prediction of the reverberation time in rectangular rooms with non-uniformly distributed sound absorption

The aim of this paper is first to review the best known
reverberation time formulae and then to show that the reverberation time cannot
be thereby predicted accurately in cases mostly encountered in practice, where
the sound field is not diffuse. Introducing a correction to Fitzroy's formula
allows better prediction of the reverberation time in the case of non-uniformly
distributed sound absorption. Comparison of calculation results obtained on both
the basis of classical equations and the new time reverberation formula
introduced is shown. In addition, the results obtained by measuring
reverberation conditions in situ and those predicted for the same enclosure are
compared and conclusions drawn.