Assessing the effectiveness of geometrically modified pyramidal diffusers: Scattering coefficient measurements

• Main Authors: Bradley, David, Sharma, Ariana, Adelgren, Jacob
• Format: Conference Proceeding
• Language: English
• ISSN: 1939-800X
• DOI: 10.1121/1.4862776

A diffuser is a surface with a non-planar geometry used in acoustically sensitive spaces to help mitigate unwanted effects from strong reflections such as echoes and focusing. Although a variety of diffuser surface geometries exist, new designs are constantly being generated for use in specific real-world projects in an effort to expand the aesthetic options available to the architect and acoustical consultant. The effectiveness of these new designs must be determined as part of the responsible acoustical design process. In the current project, the acoustic behavior of surfaces with a pyramidal base pattern has been measured according to standard ISO 17497-1. In particular, the standard outlines the measurement of the scattering coefficient, a quantifier of how much energy has been reflected away from the specular direction. This coefficient gives a general indication of the diffusing effectiveness of the surface and is useful in computational acoustics room modeling. The surface pyramidal base pattern has been varied to create an array of surfaces in an effort to find an optimal combination of geometric input parameters.