BBC RD 1990/15

THE DESIGN AND APPLICATION OF MODULAR, ACOUSTIC DIFFUSING

ELEMENTSR. Walker, B.Sc.(Eng)., C.Eng., M.I.E.E.

Research Department, Engineering Division THE BRITISH BROADCASTING CORPORATION

Research Department

Report

60th ANNIVERSARY

YEAR 1930 1990

(PH-305) 1990

BBC RD 1990/15

THE DESIGN AND APPLICATION OF MODULAR, ACOUSTIC DIFFUSING ELEMENTS

R. Walker, B.Sc.(Eng.)., C.Eng., M.I.E.E.

Summary

The requirements for and the advantages of a modular acoustic diffusing element are described. This module was intended to complement the existing range of acoustic absorbing elements already in widespread use. The theoretical background to the principles is summarised, based on the published work of M.R. Schroeder, and a design for such a module is discussed. The performance of the resulting prototype set of modular diffusers and the outcome of some field trials are described. The main difficulty, that of finding economic methods of manufacture, is also discussed.

Index terms: Acoustics; acoustic treatment

Issued under the Authority of

Research Department, Engineering Division BRITISH BROADCASTING CORPORATION Head of Research Department

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