Contribution
Mind the gap: Perceptual sensitivity to anisotropy in late reverberation
* Presenting author
Abstract:
Virtual acoustic auralizations usually compute early reflections with the image source method and synthesize them with spatially accuracy. For later reflections, the computed energy decay is often rendered as diffuse, isotropic reverberation. However, our experience shows that we can hear spatial anisotropy in reverberation, e.g. when walking past an open door. We studied the perceptual sensitivity to non-reverberant gaps in otherwise spatially diffuse reverberation in static and dynamic listening situations. Experiment 1 investigated a static situation with a direct sound from the front (0°) and diffuse reverberation from 36 horizontally arranged loudspeakers in an anechoic chamber. Reverberation times and spectral decays were modeled after an average room. A gap of variable angular size had to be detected at either 0° or 90°. Results for noise bursts show highest sensitivity to gaps in diffuse reverberation at the side (35°) and lowest (70-110° threshold) if the gap is at the front and aligned with the direct sound. Experiment 2 permitted subjects to move in the reproduction space to identify the gap location from four positions. Thresholds were similar to the static condition, indicating that orienting dynamically helps little to hear out spatial anisotropy and that the direct sound strongly masks the gap.