Comparison of an integral equation and energy and the ray-tracing technique in room acoustics

This paper deals with a comparison of two room acoustic models. The first o ne is an integral formulation stemming from power balance and the second is the ray-tracing technique with a perfectly diffuse reflection law. The com mon assumptions to both models are the uncorrelated wave hypothesis and the perfectly diffuse reflection law. The latter allows the use of these metho ds for nondiffuse fields beyond the validity domain of Sabine's formula. Co mparisons of numerical simulations performed with the softwares RAYON and C eReS point out that these results are close to each other and finally, a fo rmal proof is proposed showing that both methods are actually equivalent. ( C) 2000 Acoustical Society of America. [S0001-4966(00)02309-2].