New tube preamp

The Lamm Industries LL2.1 is an exceptional vacuum tube preamplifier you may want to add to your audition list. It's a little over budget but in exchange you could be finished with your search and find long-term happiness.

I agree that you need to hear these things in your home, in your system to be able to make a choice that leads to that long-term happiness; find a dealer that will help make that happen.

- Colin

full disclosure: I'm a Lamm Industries dealer
https://gestalt.audio

Put Prima Luna on your list...

My neighbor owns the microzotl and it is exceptional! He also owns the Don Sachs pre and it is exceptional! They are different sounding pre amps but both wonderfully musical. If your system is slightly bright or fatiguing, the Don Sachs may be the better fit. It exhibits a little more of the tube flavor to my ears. The LTA on the other tends to sound a little cleaner and neutral. They are certainly more similar than they are different. You can’t lose either way 😊 

You should try a Backert Labs Rhumba Extreme 1.3. I have the regular Rhumba 1.3 and it is very impressive.

I have the Microzotl preamp @$4500, and I can confirm that it sounds quite excellent. However, I cannot offer any comparative assessment other than I like it significantly more than the Parasound JC2 solid state preamp that it replaced.