Perceptual effects of update-delay in room auralization

Abstract

A real-time auralization system, permitting sources and receivers to move about a simulated acoustic space, offers the opportunity to study auditory perception in realistic listening scenarios. However, such a system requires substantial computing resources to achieve the low latency needed for the simulation to adjust to new conditions without introducing artifacts. To use computing resources most efficiently from a perceptual standpoint, the perceptual effects of the simulation update delays must be understood. Simulated early reflections are typically determined via the image source method. When the source or receiver moves, the positions of the image sources relative to the receiver must be updated, with higher orders requiring longer calculation times. The aim of this study is to examine the perception of sound sources in simulated reverberant rooms when a source moves to a new position with only a partial update of image source locations. The parameters tested are perceived localization and apparent source width, as a function of the highest order of image sources updated and the distance traveled by the moving source. The results are meant to aid designers of real-time auralization systems by providing a perceptual basis for the necessary update rates for image source locations. They also aim to provide insight into the perception of auditory images that are incongruous with a real room, where there is a dissociation between source and reflection positions. [Funded by BMBF 01 GQ 1004B.]