Hi @GarfieldModular, I'm splitting the stereo signal into its sum (all info, that is the same in L and R) and its diff (all info, that is different in L and R) signal. Those are mono signals of their own, and can be combined, after processing, to form a stereo signal again. That's the wonders of Mid/Side processing, a commonly used mastering techniques. In Eurorack you can do that with modules such as the Worng LRMSMSLR or Shakmat SumDif.