I think I follow your question. Increasing the gain on the pre-amp will affect the volume of the signal coming into the SMS-1, and that increase will appear in the SMS-1 output as well. It will do exactly what you hope it does - track the gain/volume of the main system and boost or cut the subwoofer independently as desired. Oh, and the default volume for the SMS-1 is remembered as one of the settings, so if you change it and want to go back to your default you can simply hit "RESET" on the remote and it will put you back where you calibrated to. It will also return to the default volume when turned off and back on (although I've been leaving mine on all the time).