A method for compensating for acoustic influence of a listening room on an acoustic output from an audio system including at least a left and a right loudspeaker, the method comprising determining a left frequency response and a right frequency response, designing left and right compensation filters, and during playback applying the left and right filters to left and right input signals. The method further includes determining mono and side responses and designing mono and side compensation filters, and, during playback, applying the mono compensation filter to a mono signal based on the left and right input signals, and applying the side compensation filter to a side signal based on the left and right input signals. The filters are thus combined to provide left and right output signals which have been left/right filtered and mono/side filtered.