The Counterpoint SA-5000 upgraded is excellent. I can do the upgrades, but I would prefer the SA-2000 upgraded as I have more room to add goodies to it and there is no floating circuit board to work with. The old Hovland tube preamp works very well with Krell amps. For non tube preamps the Tom Evans Vibe is an excellent preamp. I also build DHT preamps with no caps in the signal path and I also use Slagle transformers with TVC volume control (no resistors). I have not heard the Coincident DHT but it looks like a nice design. I agree that once you experience DHT there is no going back.
Happy Listening.
Happy Listening.