Audio Signal Decorrelation Based on Reciprocal-Maximal Length Sequence Filters and Its Applications to Spatial Sound

摘要

An algorithm of audio signal decorrelation is proposed. The algorithm is based on a pair of all-pass filters whose responses match with a pair of reciprocal maximal length sequences (MLSs). Taking advantage of the characters of uniform power spectrum and low-valued cross-correlation of reciprocal MLSs, the filters create a pair of output signals with low cross-correlation but almost identical magnitude spectra to the input signal. The proposed algorithm is applied to broadening the auditory source-width and enhancing subjective envelopment in multichannel sound reproduction. Preliminary psychoacoustic experiments validate the performance of the proposed algorithm.