Variations in the surface textures of choral reflectors

Abstract

The commission to design a portable choral reflector seemed a simple process of finding a balance between acoustical and structural requirements. Initial inquiries, however, found a lack of information on the acoustical effect of different surface textures normally used. An experiment was developed to assess both the subjective and objective performance of varying degrees of surface roughness. Eight possible surfaces were chosen and applied to standardized panels. The impulse response of each panel was measured in an anechoic room using a maximum length sequence signal. Early results indicate significant differences in the reflected energy and frequency response of the respective panels. An attempt to obtain a subjective evaluation of the reflections by convolving choral and solo voice recordings with the impulse response of the panels will be reported. A prototype choral reflector based on this work will be described. [The support of the Acoustics Research Centre for this project is acknowledged.]