I was looking to add and amp to my Denon 4806 to power a second zone. Then I thought maybe I will upgrade my Fronts(Claritys) with an amp and use the left over on the Denon to power the second zone. I am very very limited on choices in my area for local dealers to listen to much. So I would like some thoughts on How high do I have to go $$ to be a noticeable upgrade on my fronts from the Denon amp. Any ideas would be great. I have thought about tubes but I am concerned about power(Volume) and also back ground noise. I have heard that tubes will usually have a little noise and I know this is not considered a problem but it drives me nuts I like a dead quite background even when I put my ear to the speaker I want it black. Yes I know I have issues!!!