Comparison of real world measurements and computer model results for a dedicated coupled volume system

Abstract

A dedicated coupled volume system consists of a larger main space connected through an opening, or coupling aperture, with a smaller auxiliary space specifically designed to produce a double slope effect (DSE). DSE can be achieved if the absorption characteristics in the secondary space are such that its decay time is longer than that of the main space, which in turn causes late-arriving energy to be fed back into the main space. This project focuses on the verification of computer modeling as an accurate method for analyzing dedicated coupled volume systems. Impulse response measurements were taken in a real world coupled volume hall. The amount of absorption in the main hall and the number of open apertures were systematically varied to create a series of configurations for which the impulse responses were measured. The same configurations of the hall were modeled in the computer aided acoustical modeling program, ODEON. Comparisons of the impulse responses from the real world measurements and the computer model are presented both qualitatively and quantitatively through examining pertinent objective acoustical measures, such as reverberation times (T30, T15) and clarity index (C80).