Tubed Linestage

I may be upgrading from a ARC PH-3SE to an ARC PH-7. My sound has a bit of an edge to it, which the upgrade may fix. I was wondering about going to a tubed linstage and bypassing my current linestage solid state preamp. I currently have the ARC 3 going into a Theta CB3, then into 2 Krell KMA-160's with a couple of MAXX II's at the end. I read where it was suggested that ARC equipment doesn't mate well with Krell. Any comments or suggestions? I'm looking for a warm, yet clear sound. Oh-I'm using a Clearadio Emotion with a Maestro cart on the front.