Multizone reproduction of speech soundfields: A perceptually weighted approach

In this paper a method for the reproduction of multizone speech soundfields using perceptual weighting criteria is proposed. Psychoacoustic models are used to derive a space-time-frequency weighting function to control leakage of perceptually unimportant energy from the bright zone into the quiet zone. This is combined with a method for regulating the number of basis planewaves used in the reproduction to allow for an efficient implementation using a codebook of predetermined weights based on desired soundfield energy in the zones. The approach is capable of improving the mean squared error for reproduced speech in the bright zone by -10.5 decibels. Results also show that the approach leads to a significant reduction in the spatial error within the bright zone whilst requiring 65% less loudspeaker signal power for the case where the soundfield in this zone is in line with, and hence partially directed to, the quiet zone.