Blind source separation for hearing aids

An electronic filtering device for performing real-time unmixing of a signal desired to be recovered by a user of the device, where the desired signal emanates from one of a plurality of independent signal sources. Two microphones positioned along a common axis develop first and second electrical input signals in response to reception by the microphones of acoustic signals from the plurality of independent signal sources. The common axis of the microphones is controllable in real time by the user to align the common axis so it points in the direction of the source of the desired signal. An adaptive unmixing signal processor responsive to the input signals develops output signals wherein the desired signal is separate from the mixture signal. A preprocessor may be provided to subject the input signals to one or both of a time delay processing and a decorrelation processing before their application to the unmixing signal processor, to enhance recovery of the desired signal. A selected output of the unmixing signal processor can be applied as an input to a speaker for reproduction, or can be further processed for signal enhancement by an additional processor before reproduction.