A signal separator (100) for determining a first output signal (a1) describing an audio content of a useful-signal source in a first microphone signal, and for determining a second output (a2) signal describing an audio content of the useful-signal source in a second microphone signal comprises a source separator (130) for receiving the two microphone signals and for separating audio contents of at least two signal sources. The source separator (130) is designed to obtain a first partial signal (y1) essentially describing an audio content of a first signal source, and representing the first output signal, and so as to obtain a second partial signal essentially (y2) describing an audio content of a second signal source. The source separator (130) is designed to adjust parameters of a processing specification for generating the first partial signal from the microphone signal in such a manner that a distortion of the first partial signal relative to the first microphone signal is smaller than a maximum distortion, and to adjust parameters of a processing specification for generating the second partial signal from the microphone signals in such a manner that a distortion of the second partial signal relative to the second microphone signal is smaller than a maximum distortion. The signal separator further includes a signal remover for removing the second partial signal from the second microphone signal so as to obtain the second output signal, wherein the second partial signal is reduced. The signal separator offers the advantage that a multi-channel representation of the microphone signals which is corrected in terms of an interference signal may be achieved in a particularly simple manner by using a secondary condition in the source separator.