1. A signal processing apparatus for dereverberating a number of input audio signals, comprising: a memory; and a processor coupled to the memory and configured to: transform the number of input audio signals into a transformed domain to obtain input transformed coefficients, wherein the input transformed coefficients being arranged to form an input transformed coefficient matrix; determine filter coefficients upon the basis of eigenvalues of a signal space, wherein the filter coefficients being arranged to form a filter coefficient matrix; convolve the input transformed coefficients of the input transformed coefficient matrix by the filter coefficients of the filter coefficient matrix to obtain output transformed coefficients, wherein the output transformed coefficients being arranged to form an output transformed coefficient matrix; and inversely transform the output transformed coefficient matrix from the transformed domain to obtain a number of output audio signals.