I actually have the 4308 not the 4808 (don't know if there are differences). The Amp Assign outputs allow me to send a 2 channel signal to a second set of speakers (what I referred to as Front B since that's where they were). This could be done by wiring to the Surround B/Amp Assign or Amp Assign 2. I believe I had my Front B speakers wired to Amp Assign-2 but can't be sure. Since I don't have the amp at the moment, I don't recall exactly what the setting was in the menu to activate both pairs. I will have to dig out the manual to check, but i believe it was the bi-amp setting that allowed me to do this.
I was able to get sound from all 4 front speakers in any mode as I recall. Any surround sound mode or 5/7 channel stereo played fine.
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