Historical evolution of sound diffusion in spaces for modern music

Abstract

This presentation will review the historical evolution of the use of sound diffusors, from their initial use in recording control rooms to include almost all spaces for the performance, recording, and audition of music. Shortly after the invention of the reflection phase grating diffusor by Manfred Schroeder in 1973, the quadratic residue diffusor was installed in Michael Fowler Hall, New Zealand, Underground Sound recording studios in Largo, MD, and in the Oak Ridge Boy’s Acorn Studio in Henderson, TN. The initial acceptance of these new surfaces led to installation in hundreds of recording control rooms and live rooms, home theaters, stages, auditoria, and worship spaces. The design of sound diffusors was expanded to use optimization algorithms created by Cox and D’Antonio to include decorative shapes to complement the original phase grating surfaces, thus opening their use in all architectural acoustic spaces. Following a brief review of the design theory options, many applications over three decades, in a wide range of venues will be presented. A speculation on what the future holds, based on evolving diffusive designs and advanced manufacturing methods, will also be presented.