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
I have a Pass XA30.8 paired with a VAC Renaissance MK5 preamp.  Works very well together musically bolstered by design compatibility in impedance, gain, and both having fully differentially balanced circuits.  Drop a pair of NOS 6922 into the VAC and you get the quietness of a Class A SS amp paired with the tubey goodness of the VAC.  A perfect pairing in particular with speakers around 8 ohms and 90dB sensitivity in my experience.
+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.