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
@liamowen Ya this engineer in our audio discord Sonic Visions loves Conrad Johnson. Says their designs are incredible.
@JG2077 seems like the black path is the CAT to get.
@smodtactical,  see if you can audition the CAT near you.   Ask the seller if the unit has been serviced? In one of my systems,  CAT replaced an AR3. Excellent suggestions have been provided to you.  Good luck and enjoy the search. 

Best,
Jose
+1 for GAT

The Shinzo recommendation is a really interesting one. I have never heard one… but read so very much. Shindo has a small but loyal following. I am always drawn to the descriptions. I lived in Japan off and on and knowing the dedication for details and iterative improvements,  and esoteric nature of the products  is intriguing. But I have never heard of a Shindo in with say a Pass amp and B&W speakers… it sounds like if you go down that path. If I find some extra money sometime I am going to buy one for fun and see where it leads.