Psycho-acoustic evaluation of physically-based sound propagation algorithms

Abstract

Recently, many physically accurate algorithms have been proposed for interactive sound propagation based on geometric and wave-based methods. In terms of these applications, a key question arises whether the improved physical accuracy of these algorithms offers perceptual benefits over prior interactive methods? In this work, we present results from two studies that compare listeners' perceptual response to both accurate and approximate propagation algorithms that are used to simulate two key acoustic effects: diffraction and reverberation. For each effect, we evaluate whether increased numerical accuracy of a propagation algorithm translates into increased perceptual differentiation in interactive environments. Our results suggest that auditory perception indeed benefits from the increased accuracy, with subjects showing better perceptual differentiation when experiencing the more accurate propagation method. The diffraction experiment exhibits a more linearly decaying sound field (with respect to the diffraction angle) for the accurate diffraction method, while the reverberation experiment shows that more accurate reverberation results in better assessment of room volume and acoustic distance perception. In case of room volume, accurate reverberation, after modest user experience, results in a near-logarithmic response to increasing room volume. Finally, in the case of acoustic distance perception, accurate reverberation shows less distance compression as compared to an approximate, filter-based reverberation method.