If you're using a Hartke, I highly recommend upgrading the passive components in the tube preamp--better caps and resistors really improve the warmth, clarity, and definition. I've done a couple of these lately and they kinda made me nostalgic for my old 7000, possibly because it accomplished in 2 rack spaces what I'm now doing in 4. Of course, my new rig sounds better, but I have to wonder if anyone but me (or one of you guys!) could tell the difference.