The invention relates to a method and the associated device 1 for separating one or more particular digital audio source signals (si) contained in a mixed multichannel digital audio signal (smix) obtained by mixing a plurality of digital audio source signals (s1, . . . , sp). According to the invention: the modulus of the amplitude or the normalized power of the particular source signal(s) (si) is determined from representative values of said particular source signal(s) contained in the mixed signal; and then linearly constrained minimum variance spatial filtering is performed on the mixed signal in order to obtain each particular source signal (s′i), said filtering being based on the distribution of said particular source signal between at least two channels of the mixed signal, and the modulus of the amplitude or the normalized power of said particular source signal is used as a linear constraint of the filter.
