Influence of a volume scale factor on the scattering coefficient effects on the prediction of room acoustic parameters

Abstract

Surface scattering has become an important input parameter in the work on geometric models and in the research concerning the enhancement of auralized sound. This contribution deals with the comparison of four scaled prediction models of the same concert hall and studies the scattering coefficient prominence in simulations while the size of the concert hall increases by two, three and four times. The hall is a fan shaped hall with aspect ratios of around 4.5:2.8:1 and typical auditorium features such as stage and raked audience area. The influence of a volume scale factor on the scattered sound effects on the prediction of the objective room acoustic parameters like T30, EDT, C80, D50, LF and G, is investigated. Five different alternatives were simulated, where scattering coefficient values s = 10, 30, 50, 70 and 90% respectively, were applied separately and combined to the interior surfaces of the ceiling, side and rear walls. Analysis has been performed by studying the results of objective room acoustical parameters predicted by simulations done with software Odeon R 11.00 and Catt-Acoustic R v 8.