Optimization of temporally diffuse impulses for decorrelation of multiple discrete loudspeakers

Abstract

Temporally diffuse impulses (TDIs) were originally developed for large arrays of distributed mode loudspeakers to achieve even radiation patterns. This initial investigation evaluates the performance of TDIs in terms of the reduction of low frequency spatial variance across an audience area when used with conventional loudspeakers. A novel variable decay windowing method is presented, allowing users control of TDI performance and perceptibility. System performance is modelled using an anechoic and an image source acoustic model. Results in the anechoic model show a mean spatial variance reduction of 42%, with a range of source material and using the optimal TDI generation methodology. Results in the image source model are more variable, suggesting that coherence of source reflections reduces static TDI effectiveness.