Auditory spatial impression in concert halls

Auditory spatial impression is one of the important characteristics perceived in concert halls. The author defines the term auditory spatial impression as the spatial extent of the sound image. Auditory spatial impression comprises at least two components. One is auditory source width (ASW) which is defined as the width of a sound image fused temporally and spatially with the direct (preceding) sound image and the other is listener envelopment (LEV) which is the degree of fullness of sound images around the listener, excluding a sound image composing ASW. A listener can perceive these two components separately. This paper reviews key results of many listening tests on the effects of spatial and temporal structures and spectra of reflections on ASW and LEV by the author.