What tube pre-amps pair well with Pass amps?


Does anyone have experience with this?  I'm running Focal Sopra No. 2s and I understand the Focal's pair nicely with Pass amps.  Any tube pre-amps you'd recommend for consideration? I like the classical rock, but am gravitating more to jazz, classical and vocals. I just want to try something new.  Thanks.
billtro
For many very satisfied years, I had a Pass Labs X 250 paired with an Audio Research Ref 1...I never wanted anything else until I down-sized to a smaller house and listening room...
I am happy with my Audio Research Ref 6 pre and Pass Labs XA 60.8.  Can buy the Ref 6 used.
The LSA website recommends speaker sensitivity as:

Critical listening environments: 105db sensitivity and above

Smaller rooms / lower volume levels / non-critical listening: 97db sensitivity and above.

Aren't those levels speaking to horn speakers?