Quantitative expression of spatial impressions for sound image.

Abstract

In order to achieve quantitative measurement of spatial impressions of sound image, a method using masking pattern, spatial difference of masking level, is proposed. Masking patterns of real and phantom sound image are measured as a lowings:(1)the masking patterns correspond closely to the spatial impressions of the sound image, (2) the maximum of the masking patterns coincides with the azimuth of the sound image, (3) the width of the sound image can be interpreted by the masking patterns. The phantom sound image for the white noise whose cross-correlation (γ) is equal to 1 is wider than the real sound image localized in front of the subject. The phantom sound image for noise with γ=0 is almost as wide as the distance between the two loudspeakers, (4) the phantom sound image for the white noise with γ=1 is localized higher than the real sound image localized at the same height as the subject's head, (5) the masking patterns of the sound image reproduced through headphones correspond to the spatial impressions fairly well.