Need recomendations on Pre-Amp / processor

I currently have a Chiro C800 Pre-Amp aith DTS decoder. I use the system for home theater and 2 channel stereo. The stereo portion is very important to me and I'm looking for an upgrade to my Chiro.

The rest of my system is: Krell 5 ch amp, Sony DVD, Dunlavy SCIVA and HRCC speakers.

Thanks for your help. Looking for something on the used market that can do DTS AC3 and the future?