OK, so you are building a music only system and you want an AVR? don't listen to these guys, lol... MUSIC ONLY, NO video circuits allowed...
OK- not sure if there was a real budget yet, but here is what i would do low budget..
SVS SB-1000 - 300 Watt DSP Controlled, 12" Ultra Compact Sealed Subwoofer - nice musical sub, will do the job fine and guess what? handles your bass management...
this dac
Amazon.com: Audioengine D1 24-bit Digital-to-Analog Converter: Computers & Accessories
then pick any amp from my previous post, if you can stretch the budget, go with an emotiva upa200, you will have it for a long time and it wont be quickly outgrown....
An AVR would work, I just think its a waste and I am in the NO AVR club, but no matter what you do it will work fine I am sure of it...
I am not sure if you have a best buy near you but the pioneer elite vsx43 is on sale today for $279.99 My buddy bought one today...