I could probably get a used Parasound 855A for less than or around $500, would it be a great jump in improvement over my current amp in my 797, especially in music. The 797 sounds great in music, but I used to be a stereo only guy, and would like a little more. I don't want to get a 2 ch amp because it was said that my front soundstage may sound awkward, but the reason is that my front towers are 4ohms, and at volumes a little over refrence, the Onkyo does strain sometimes in Direct mode without the sub to relieve it of low frequency challenges. So will it be a big improvement, or am I dreaming at this price? Any other suggestions for a $500 5 channel amp(new or used)?