Agreed, DSPs are not a problem. But you can't get stereo if you are using one amp (one channel) to feed the backbox and one amp (the other channel) to feed the cabinet speaker. Not being familiar with the actual design, if it is like WPC games - they use a low pass filter to take out the high frequencies and pass only the lows to the cabinet speaker, and then a high pass filter to take out the low frequencies and pass them to the backbox speakers. I don't know if that is what Stern does with the latest or not, but the whole back end of the chain would need a change in design if you are using one pipe of signal to the backbox speakers.

I was right that a pinsider would have a mod

Thanks!!!