Polycylindrical Diffusers in Room Acoustic Design

Abstract

Recent acoustic design of studios, auditoria, and other enclosures has led to the use of polycylindrical wooden surfaces for obtaining a more uniform decay of sound and for minimizing the detrimental interference effects due to first reflections. A comment often made in first walking into a room with polycylindrical diffusing surfaces is that it “feels” or “sounds” larger than the ordinary room with parallelepiped construction. To obtain the maximum diffusing action in the direction of the three orthogonal planes, the axes of the polycylindrical surfaces should lie mutually perpendicular to each other. The major dimensions of the enclosure should preferably be in the ratio of the cube root of two or in even multiples thereof. Charts and illustrations of typical applications of the diffusers will be given.