Implementation of a Highly Diffusing 2-D Digital Waveguide Mesh with a Quadratic Residue Diffuser

Kyogu Lee, Julius O. Smith
Center for Computer Research in Music and Acoustics (CCRMA)
Music Department, Stanford University
{kglee, jos}@ccrma.stanford.edu

Abstract

In concert hall acoustics, the reflection characteristics of the ceiling and the walls are important for minimizing the interaural cross correlation. Many design methods have been presented so far in order to design highly diffusing surfaces. This paper presents a two-dimensional digital waveguide mesh having a highly diffusing boundary using quadratic residue sequences, and illustrates its reflection properties. Empirical analyses show that high diffusion occurs at the diffusing boundary, and the scattering characteristics show the energy of an incident plane wave is evenly scattered in a mesh with a diffusing boundary while a specular reflection occurs in a mesh with flat surfaces.