I agree with Pojuojuo and Audiooracle. I was using the Denon AVP for two channel. Like the Krell, it has a bypass which allows a pure analog signal to pass through. While it was pretty good, I decided to try a line stage that had an HT bypass. I hooked up my two channel stuff to an ARC LS27. As stated by Audiooracle, it was no contest.
Before you change the speakers, try out a preamp/line stage that has an HT bypass.