Sound Decay Analysis in Acoustically Coupled Spaces Using a Re-Parameterized Decay Model

Abstract

Abstract. The sound energy decay characteristics of coupled spaces are of increasing interest to architectural acousticians. Coupled spaces occur naturally in concert halls and theaters due to the presence, for example, of balconies, orchestra pits, and stage houses. In addition, many new halls have incorporated hard chambers coupled to the primary space to achieve a flexible variation of the acoustics. In certain conditions, sound energy in these coupled spaces decays with two or more distinct exponential rate constants. The presence of multiple decay rates can have a distinct impact on a hall's perceived acoustical quality. In previous papers [1, 2] we describe our initial work to apply Bayesian inferential methods to the problem of determining multiple decay times in coupled spaces using Schroeder energy decay functions derived from measured room impulse responses. In our previous work, relatively little prior information about parameters of the decay model is incorporated in the inference calculations in spite of the fact that much information regarding both the possible range of the parameters and the relationship between the parameters is known. In this paper we describe our recent efforts to incorporate this prior information into the inference calculations by re-parameterizing the multi-exponential decay model.

Using Nested Sampling in the Analysis of Multi-Rate Sound Energy Decay in Acoustically Coupled Rooms

“…The application of Bayesian inference in the acoustics of coupled rooms has been well documented in a series of papers by Xiang and Goggans [6]- [8] and Goggans et al [9]. Figure 2(A) and Figure 2(B) show plots of the likelihood function for the decay models of decay order two and one respectively which are denoted by H 1 and H 2 , the boundary of the plots also define the range of a normalized prior π(x|H i ) used in each calculation.…”

Bayesian characterization of multiple-slope sound energy decays in coupled-volume systems

“…The applications of fully parameterized decay models for this purpose in room-acoustics energy decay analysis can be traced back to Ref. 32, and more recently in the work by Jasa and Xiang, 19 however, the advantage and necessity of using fully parameterized decay models has not yet been articulated for this application. After a brief formulation, Sec.…”