The Significance of Spectral Overlap in Multiple-source Localization

The mechanisms of human localisation for a single sound source are well understood, but less is known about how we localise multiple, simultaneous sound sources. In rendering a complex virtual auditory space (VAS), localisation cues are applied separately to each sound object and the results are summed to create a multiple-source environment. In this paper we investigate the relevance of the inter-source spectral overlap that arises in such a VAS. We do so by adjusting the spatial cues in these regions and comparing a listener's localisation ability for the modified and unmodified cases. We show how even total removal of the weaker spectral components in regions of overlap has no effect on localisation ability. Finally, we discuss the exploitation of redundancies in the regions of spectral overlap with respect to multiple-source localisation.