He could just buy a nice A/V receiver now and add separate amps later, no?

I believe someone at Axiom told me that the procesors in my Denon receiver are quite good and I know it is capable of 7.1. I was thinking about using it as processor later if I really got geeked out on this stuff. In that case would it always sound like my current system? or would the sound take on the flavor of the new amps? or a combo of both?