Coherent modulation spectral filtering for single-channel music source separation

Modulation spectral filtering, if effective and distortion-free, would offer a new tool for signal modification. Previous approaches to modulation spectral filtering, which made use of incoherent detection of real and positive modulating envelopes for each frequency sub-band, have not offered effective and distortion-free signal modification. Based upon a recent observation that the modulating envelopes are potentially complex, coherent detection is instead proposed. Details are provided for accurate carrier estimation, and tests on both synthetic signals and music, show that modulation filtering is indeed distortion-free. The coherent modulation filtering method is applied to single-channel music sound source separation with promising results for music and other signal separation and modification applications.