PS Audio BHK Signature Preamp?

I’m running mine with Gold Lion 12au7s. The stock PSvanes sound wonderful as well. Not too much difference in sound between the two that would really make one take notice. 

I bought the BHK on 3/23/2020 and later on replacing with two brand new NOS telefunken tubes, wow, I can hear the sound is more beautiful. It is a good preamp.

Hopefully, that will help.

Purchased mine in 2021and extremely pleased

The input stage is tube based and the output stage is solid state

I've experienced deeper, wider, sound stage, an increased separation of instruments and an overall wider dynamic range of highs and bass

Good products made by a good company, IMO

@stevewharton An impressive endorsement. Which preamp(s) are you comparing with the PSA?

I had the PS Audio BHK about 2 years ago.  It replaced an Ayre K5xeMP.  The stock tubes were awful IMO.  The preamp was bright and I found awful with stock tubes.  Rolled in NOS Tunsgrams and it was sweet and engaging.  Step up from the Ayre.  It was paired with VTL MB185s and a Rogue Audio Hydra.  

I have since had a few preamps that I think are as good or better.  The AVM PA 5.2 is as good with a better feature set like tone controls and optional cards.  The Art Audio Conductor (much more expensive SE preamp) was significantly better with my Art Audio and Rogue amps.  

The PS Audio is best in a fully balanced environment with fully balanced DAC and power amps.  I would not bother if you have SE amps.  You will almost certainly want to roll tubes.  You will find quite a few different choices but I had great luck with the NOS Tunsgrams.  You should be able to find this used for ~$3500 and is a strong value at that price point.