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
+1 on the LTA  MZ2 with a XA30.8.  This is a very good pairing and drives my Vandersteen Treo CT’s with finesse and power.
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Linear Tube Audio Microzotl Reference Pre-Amp.  It's a wonderful piece of gear.
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...