The present invention provides methods and systems for digitally processing audio signals in two-channel audio systems and/or applications. In particular, the present invention includes a first filter structured to split a two- channel audio input signal into a low frequency signal and a higher frequency signal. A M/S splitter is then structured to split the higher frequency signal into a middle and a side signal. A detection module is then configured to create a detection signal from the middle signal, which is used in a compression module configured to modulate the side signal to create a gain-modulated side signal. A processing module is then structured to combine the low frequency signal, middle signal, and the gain-modulated side signal to form a final output signal.