1. A method for removing convolutional noise arising over a communications channel from an audio signal, the method comprising: a. characterizing the signal with respect to a plurality of frequency bands, the signal having a power in each frequency band; b. computing a logarithm of a quantity characterizing the power of the signal in each frequency band over a specified interval of time for deriving a transform of the signal in a log-spectral domain; c. fitting a smoothed log-power spectrum to the transform of the signal in the log-spectral domain for deriving a fitted log-power spectrum corresponding to the effect of convolutional noise in the log-spectral domain; and d. removing a function of the fitted log-power spectrum from the transform of the signal in the log-spectral domain, so that convolutional noise has been removed from the transform of the signal.