Originally Posted by rbinck
It would be better to connect the 2 SA-2 woofer amps to the sub-woofer output of the Yamaha RX-V2400 with a splitter at the Yamaha RX-V2400 and the two you show at the SA-2s. Then set the crossover in the Yamaha RX-V2400 according to the speaker recommendations. Also it may be that you only need to feed the left channels on the SA2s when satellites are not connected to the SA2s thus eliminating the splitters at the SA2s.
Also you will need to match the SA-2s low and high pass filters to match the crossover frequencies. It may take a bit of trial and error to get this right and it may be best to set the subwoofer a 150 hz and the satellites at 110. That would let the Yamaha RX-V2400's setting have the crossover control.
I am also running a sa-3amp and sw-3 subwoofer on the system which I am using the sub pre out on the yamaha for.I see what your sayin as for as the rest goes.well the bi amp process make a notable differnce?Is the rest of the diagram correct also?