Physical and subjective factors of spatial envelopment impression of surround sound reproduction

Abstract

How we feel the envelopment of reproduced sound? For the evaluation of spatial impression, “envelopment” is one of the key factors among several attributes in audio reproduction. In the authors' past research, three attributes were elicited from participants regarding surround sound reproduction using triadic elicitation procedure. The three attributes are “brightness,” “temporal separability,” and “spatial homogeneity of envelopment.” In this paper, authors focused on “spatial homogeneity of envelopment” and considered related physical parameters such as ESC (ear signal correlation; defined as the correlation between left and right ears' signal). From comparison between the result of subjective test and the data measured with a dummy-head facing toward different angles, it was found that the correlation between the ESC of different head angles and the amount of differences of ESC from focused sound to diffused sound contribute the sense of “spatial homogeneity of envelopment.”