Subjective impression of spatially distributed reverberation in multi-channel audio reproduction

Abstract

Auditory immersion and spatial impression in multi-channel audio reproduction can be altered by changing the number of loudspeakers and independent reverberation channels. The spatial impression can change drastically as one moves away from the sweet spot. Since multi-channel audio reproduction is not limited to one position, it is critical to investigate Listener Envelopment (LEV) and immersion at off-axis positions. This work discusses the impression of spatially distributed decorrelated reverberation at on and off-axis positions. Rensselaer Polytechnic Institute’s Collaborative-Research Augmented Immersive Virtual Environment Lab- oratory (CRAIVE-Lab) is used to reproduce diffused sound field in the horizontal plane through 128 independent audio channels. Results from psychoacoustical experiment show that there are perceptible differences even at higher channel counts. However, spatial impression does not change significantly beyond 16 channels of decorrelated reverberation and equally spaced loudspeakers at on and off-axis positions.