Best 6NS7 Preamp for a Pass Labs XA25 amp

Great, thank you all very much. Just what I am looking for.
One advantage of buying a product marketed for 3 years now.
ARIC 1,650
DON 2,650
DEHAVI 2,995
SUPRATEK 2,300

I heard from a guy with the xa25 who has both the supra
and a s.s. diy kit designed by wayne coburn. cost 200 for parts.
He likes the clarity of the ss more, 
I may do the diy for now and when i miss the remote
too much, buy a solution model.

There are plenty of used low cost solid state preamps that offer “clarity”, if that’s what your looking for. The original post reads “Best 6SN7 Preamp...”

Few or none of those SS kits will match the musicality of a really good 6SN7 tube based preamplifier worthy to match up well to a Pass Labs XA-25 amplifier.

I agree with mboldda1

The Ultraverve never fails to amaze me.  I use mine with a vintage 5692 6sn7 military tube.  It also sounds great with the usual suspects: Tung sol round plate GT, Raytheon vt-231, Sylvania W,  Kara, the designer of the Ultraverve is very responsive to questions, upgrades, etc. She recently upgraded mine with Dueland caps. I run it through my Bryston 14bsst.  Highly recommended!

I have a Supratek Sauvignon that uses the 6SN7. Sounds really good.
I also have had a chance to listen to "The Dodd" battery preamp hooked up to my XA-25. Incredible. would have loved to had a longer listen. I think it uses a 6922. I'm going to roll a few through the Supratek in the next few months and see if I can get a little more air. 

pfeiffer - May I ask you which Dueland caps she used and did you send your unit to Kara herself to do the upgrade?  Also, how would you describe the sonic change from the original caps which I assume you were using before the upgrade. Thanks!