Reproduction of Simulated Acoustic Scenes for Clinical and Hearing Research in a Reverberant Room Using Four Horizontal Loudspeakers

When reproducing a virtual acoustic environment over loudspeakers within a reverberant playback room, the acoustics of the playback space can modify the spectral and spatial properties of the virtual environment considerably. Traditionally, optimal loudspeaker rendering of such scenes requires dedicated loudspeaker setups positioned in an anechoic room, employing techniques like Vector-Base Amplitude Panning (VBAP) to render virtual reverberant sources, or Higher Order Ambisonics (HOA) to render spherical harmonics each using a large number of loudspeakers. In this study we will evaluate to what extend it is possible to reproduce virtual acoustic environments using only a limited number of loudspeakers placed within a normal echoic room. Recently we proposed a perceptually-based method using only four loudspeakers that specifically aims to compensate the detrimental effects of reverberation of the playback room by separately reproducing optimized versions of the direct and reverberant sound fields 1. In this study, this approach is explained in more details and specifically an important parameter that controls the power ratio between direct and reverb sounds is investigated in detail using objective and subjective evaluations. In listening tests, the similarity of this proposed Acoustic Room Transformation (ART) method is compared to that of a reference rendering of the virtual acoustic environment within an anechoic room. The results of listening tests show significant improvements in the timbral and spatial characteristics of reproduced sound using the ART method compared to conventional playback without room compensation and show a closer match to reference simulated environment.