Effects of Surface Diffusion of Reflectors on the Acoustic Power from the Stage Area

Abstract

When a sound source is located near a large plane-surface reflector, the total acoustic power radiated from the source including the reflection depends on the source position. Interference is the cause of this phenomenon, and the musical instruments for bass sound are particularly influenced. The surface diffusion treatment of the stage reflectors may be a solution for improving the problem. In this paper, from the viewpoint of acoustic power from the stage area to the audience area, the effect of surface diffusion of a stage rear-wall is examined by using an analytical model of 2 and 3-dimensional wave theory. As a result of some numerical examples, it is shown that a rear wall tilted more than right angles has a potential of improving the effect.

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