The F_COMx2 module has two full COM modules on board.

The COM module is sort of end-of-the-line module. It has stereo IN- and OUTputs, a VOLume knob and knobs for Bass, Middle and Treble. It will color your output because each of B, M and T has its own influence on the INput signal. This could be the last module used for connecting to the MAIN OUTs