"Audio refinement has pre outs that can be used for this feature. But, not the main-ins. Do you really need that if you are using a powered sub?"
Only if you plan to use the crossover in the sub to "strip" the low frequencies off, send only the high passed signal back to the amp. This should allow the amp to not have to work as hard since it will not be reproducing the low frequencies.
Of couse you could just use any integrated that has a set of line level outputs. Run the integrated full range to the main speakers and use the sub to "fill in" the bottom end.
Enjoy,
TIC
