I'm using a HarmonKardon AV, about 5-6 years old, pretty sure it's the AVR75 (I'm at work right now-can't check). The subwoofer is xo'd for 72hz.
The 6.9sm's were driven by an old 125watt JVC receiver before this one, and just sounded SO much better, even on a cheaper RC, so I'm pretty sure this one just doesn't have the guts for it.
My budget is low, anything over $500 and the spouse hackles raise higher and higher..
The other option I'm looking at is offing the HK RC on ebay, and buying a new RC with more juice, but I imagine with the combined budget of the pittance I could get for the older HK and my current spending cash, I wouldn't be able to get anything any better.. That's why I'm attracted to cheap dual monoblocks or a stereo amp.