First tube preamp recommendations (under $5k)


Right now have di20he -> terminator -> he9 -> pass x350.8 -> ATC scm7 / NS5000.
I am thinking of introducing some tubes into my chain. I like the sound I am getting but want to explore what tubes can do to the sound (slight warmth, biggest soundstage, better layering etc etc). Don’t want to go to nuts on price. If price is over $5k would consider if its really exceptional (but for sure not over $10k). Totally fine with used. Balanced would be nice but not mandatory.
So far I am thinking RP7, EVO400, bhk. Any thoughts?
smodtactical
I’d stay away from some of the very boutique brands. If you decide to move on you may find it hard to sell. If I were you I’d go for Audio Research. It’s well built, is desirable on the used market and sounds terrific!

Audio Research made a lot of different preamps. They aren't all the same. I have an LS 26. It's very nice but it's not in my main system. If I had a Ref 5SE or higher, that might be in the main system. I had a Modwright LS 100 in the main system for a long time until I recently replaced it with a "boutique" Herron Audio VTSP-360. It's a keeper. 



If you listen to records, the CAT Preamps have an excellent phono stage as well as line stage. The only drawback is that the volume control is stepped, but the quality of it is unbelievable. They are built to last.
Audible Illusions.  L3A (which is what I own) or the newer L3B.  These are line stage only, that use only 2 6H23 tubes. Or, if you want phono stage included, M3A, or the newer M3B (4 6H23 tubes).
ive owned my L3A now for about 5 years, and have not had one issue.  The sound is wonderful, but be advised this is a single ended preamp (RCA only inputs and outputs) there are no balanced inputs or outputs.