Uncertainty in scattering coefficient measurements of sintered ceramic tiled surfaces

Abstract

The reflection of acoustic energy in an enclosed space can sometimes lead to undesirable effects, particularly if the reflection is relatively large in amplitude or delayed in time. To mitigate these effects, surfaces with non-planar geometries, which are known as diffusers, can be employed in an architectural space to improve the acoustical qualities of the space by attenuating these harsh reflections and by producing a more evenly distributed sound field. One of the standardized quantifiers used to characterize the effectiveness of a diffuser is the scattering coefficient, which is defined as the ratio of non-specularly reflected energy to total reflected energy. Measuring the scattering coefficient requires a carefully controlled acoustic testing facility known as a reverberation chamber. These chambers often have attributes that can be difficult to control (e.g., humidity) or that do not adhere to the standardized specifications (e.g., size). The current study explores the uncertainty associated with a series of measurements focused on testing the effectiveness of a new type of diffuser, which has been created using a novel ceramic sintering technique. The scattering coefficients of several of these ceramic surfaces have been measured in three different reverberation chambers with varying results.