When deciding to buy my RV-8, I auditioned one driving speakers with it's internal amplifier, and then through an LX-7 amplifier with the RV-8 feeding it as a preamp. Although there was some time for "switching" involved (it wasn't an easy A/B switch), I couldn't hear any difference, so I figured this AVR was good enough to my ears.
My AVR is rated at 140W per channel into 8 Ohms fully driven, and the LX-7 was 200W per channel I think. So I'm sure I would have heard a difference once the RV-8 was pushed current-wise past what it could deliver, where the more powerful separate amp would give a little more. I guess we didn't get it that loud in our testing, but it was plenty loud enough.
