ASA 124th Meeting New Orleans 1992 October

5pAA7. Predicting the absorption of pew cushions.

J. S. Bradley

Acoust. Lab., Inst. for Res. in Construction, Natl. Res. Council, Ottawa, ON K1A 0R6, Canada

Previous research has shown that the sound absorption of arrays of theater chairs is related to the ratio of perimeter-to-area of a sample of chairs [J. Acoust. Soc. Am. 91, 1514--1524 (1992)]. Measurements of various sized samples in a reverberation chamber can thus be used to predict the expected absorption of a large array of chairs in an auditorium. This paper examines the related problem of predicting the absorptive effect of adding cushions to wooden church pews. The absorptive effect of the pew cushions was measured both in a reverberation chamber and in a church. Tests in the reverberation chamber included various sized samples of pews both with and without the pew cushions. The absorption of the pew cushions was also measured on the floor of the reverberation chamber without the pews. The added absorption of pew cushions is influenced by the presence of the pews, is largely independent of the pew sample size, and is predictable from reverberation chamber measurements.