Increased scattering efficiency through cell optimization in acoustic diffusers

This presentation will provide test data, experiments and analysis in showing the interaction of absorption and diffusion characteristics. It will be shown that absorption, either additive or design inherent, has an adverse effect on the efficiency of the acoustic diffusers. The effects of low frequency interference on various cell structures of quadratic residue diffusers will be highlighted as a prime example of this theory. The inclusion of additive absorption i.e. fabric, fiberglass and other materials, further complicates the matter of diffuser efficiency. While design characteristics of some diffusers, such as prime root and quadratic residue diffusers, can be used effectively for their absorption coefficients, overall these characteristics detract from the efficiency of the diffusion coefficients. Product designs utilizing optimized cell designs to inhibit absorption in diffusers will be shown. It will be shown that this cell optimization dramatically increases the efficiency of the diffuser. This optimization includes both higher scattering coefficients and smoother frequency responses. Comparative analysis will be provided with traditional designs and newer, optimized designs.