Pass Labs Preamps with tube amps?

I have a lot of experience with Pass. They make great amps and ok preamps. This is like riding up the pacific coast highway on a bike South to North… against the wind all the way. 
 

To find a great preamp to match an amp, I would look to Audio Research, VAC, Conrad Johnson… then decide on your amp. 

I have aa Pass XP10 and Pass 250.8- and Audio research REF150SE amp and the LS28SE pre amp; speakers are Wilson Sasha 2. I switch around combinations of the gear every few months to save hours on the tubes in the ARC and or heat generation - sound. The Pass XP10 is good- quiet, built well and neutral sounding. I can't say it's very exciting or musical. More like a functional unit that neither adds no detracts from the music. I wouldn't look to use it as a pre on a tube amp, I think it'd limit the purpose of using a tube amp by being to neutral, almost dry sounding. I do suggest the reverse though- running a good tube pre amp like the ARC LS28SE or REF 5 into a solid state amp like the Pass - this combo sounds great. 

Normally a SS amp then a good tube preamp 

check out Linear Tube Audio they make a excellent tube preamp 

with 6sn7 , plus additional tubes you can use , if xlr you can get too theLundahl C core transformer option  , exceptionally well made David Bearning helped design 

and today improved better still.

I had XP12 paired with Rogue ST100 and it was a good combo. The Rogue amp was a bottleneck but not because it’s tubes.
I run XP22 with X260.8 mono amps now and the synergy is great and I do not miss tubes.
As to the comments above claiming Pass preamps fail, I disagree. I had an Audio Research Ref 6 for over 3 weeks in my system and did plenty of A/B with the XP22 and ended up actually preferring the Pass preamp. I’m a fan of ARC and owned several of their preamps over time. But to my ears in my current system the XP22 is a better choice.

+1 @ghdprentice 

I have owned XP-30 and XP-32 preamps feeding into a very good set of SET hybrid monoblock, not quite satisfactory.  IMO Pass is an excellent amplifier company comparable in their price range, and make just alright preamplifiers.  Again YMMV.