SoCal I'm not familiar with the Yamaha receivers so therefore I'll sidestep that side of the question.
The Rotel 1080 is very sufficient for driving the 80s. I have a 1080 connected to the preouts on an H/K receiver driving a pair of 80s for the mains and use the receiver to drive the center and surrounds. Works great.
Check out this thread from the Audioholics site, there may be some useful information in there for you.

Rick
Our Room

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