Binaural signal analysis of diffuse sound fields

Abstract

The simulation and the binaural recording of sounds produced by large crowds and rain impact sounds has produced an unexpected result. The listeners have reported that the auditory events were mainly concentrated to the left and to right, although the sound sources were equally distributed around the listeners. A similar result was reported with binaural recordings of applause. The results of a binaural signal analysis suggest that the key aspect regarding the lateral position dominance of the auditory events is connected to the sections where the cross-correlation coefficient assumes negative values. A comparison between normalized and non-normalized cross-correlation function predictions indicates that the latter is a better predictor for the cases studied. An adaptation period of several seconds was reported by several listeners. It is suggested that this adaptation period is related to the variations of the cross-correlation, which only average out after, approximately 2 s. The binaural impulse responses of a concert hall at two different listener positions have been analyzed in the light of the previous findings. In particular the diffuse sound field buildup will be analyzed in detail. Implications for the auditory source width and listener envelopment will be discussed.

Auditory Virtual Environments

“…Furthermore, signals presented at the listeners' ears in (partial) phase opposition may evoke two distinct and extended auditory events [10]. This phenomena was, in fact, experienced by listeners immersed in a diffuse sound field as twin extended auditory events located symmetric to the listeners' median plane [71][72][73]. The precise location of the auditory events is head-size dependent, e. g., a child or an adult head.…”