A multichannel full-duplex audio signal transmission system, comprising an adaptive filter (2) provided for multichannel acoustic echo cancellation. A channel combining device (5) is provided between the preprocessing units (V1, . . . VD) and loudspeakers (L1, . . . ,LD), in which several (C>D) loudspeakers can be connected to one and the same preprocessing unit and by means of which the remaining D-C preprocessing units can be separated from the loudspeakers (L1, . . , LD). The channel combining device permits an optimization of the convergence ratio of the adaptive adjustment of filter coefficients in said adaptive filter (2).