I've got a pair of AR90's. I'm driving them with a Harman Kardon HK3490 receiver (120w:89ohms/150w:4ohms). If your source is a turntable, the 3490 is definitely enough power. It's around $400 new price. Mine is B stock which I bought from the factory on ebay where they are auctioned off for $229. There was a reserve at the time--they didn't call it a reserve, but you couldn't get it for less than that. The sound is really nice with the 90's. I like it a lot.
