unity gain active tube preamp?

A used Musical Fidelity X-10v3 tube output buffer.

shredder

"If you want that tube warmth"
Yes this is good but you need to also get a passive VC (volume control) before it. More $$$

Musical Fidelity have the same circuit in their Xcan-V3, but with normal size tubes, not the mini 6112 that are in the X10-V3.

But you get with the Xcan-V3, a passive volume control built in, and a headphone jack as well.
So this Xcan-V3 has all you need, but both units do have just a touch of gain (1 or 2db) above unity.

Cheers George

Why not have a custom SET- DHT  preamp made for you ? I have a SET with only 
1- stage is by far the purist active stage you can get .100% Transformer coupled 
Lundahl, orMonolithe , Tango,or whatever your budget could afford . Myself 5 transformers ,3 choke filter supplies ,all 4- pole output caps and bypassed with MundorfSilver oils the latest Shunt,relay remote from Khozmo. No coupling capacitors at all in the signal path.
Amorphous core Audio output transformers , Silver  if your budget can go the extra $2k Mile. Something to ponder though the Russian 4P1L tube is considered by many one of the most linear with lowest plate resistance but still have plenty of gain . Did you know the Vast majority of preamplifier have 2 ,or more stages 
indirect triodes .mean double the circuitry,and wiringplus regulators . You would have to spend well over $10-15k what this DHT can accomplish in purity for $6k.
No commercial markup .myself being in the Audio business before know the production markup and only 25% of the cost at most goes into the product ,including the case. Custom over 70%  goes into the build and the parts quality 
is  Much higher - premium quality.Nothing was spared in the build process. Longevity,as well as lower distortion is the 
final result of precision hand built engineering . It took me over 30 years to except 
this fact but true .Amplifiers are another animal all together they are Loudspeaker dependent . 

Custom is an interesting idea. I will look into Music reference. Any others your recommend? 

After a quick search, Tube Audio Lab looks interesting.

Further about the  Schiit Freya that was already mentioned:  It is balanced.  Has pure passive and JFET buffered unity gain output options.  Also has 6SN7 tube output with significant gain (13 db?) as a third output option.  Has finely adjustable volume control.   The price is very reasonable.

Someone from audiocircle asked NickT at Schiit, the Freya tube output gain is 10 dB single-ended and 20 dB balanced.
Maybe the tube section can be modified to unity gain?