Preamp 6922 tube help

I haven’t rolled 6dj8 equivalents in a long while, but I preferred to Tele to the Siemens, even though the Siemens was probably the more linear tube, the Tele sounded more 3d in the mids. I suspect it was the character of the circuit. I think the "right" tube for you is perhaps even trickier since you are compensating for the aggressiveness of the DAC.
Brendan at TubeWorld, already mentioned, has a pretty good handle on the sound character of NOS tubes and as I recall, he does allow a return.
I’ve used him for years and he’s proven to be a reliable supplier.
I struck gold recently with the Tubemonger- he had some NIB Genelex (GEC) EF86 tubes that were flying lead types that he converted to "normal" tube pin bases. These complement the GEC KT 66 power tubes that I got from Brendan (not easy to find either) for a pair of vintage Quad II amps. I’d reach out to both shops and get some advice.
I roll very little in my main system these days-- the odd rectifier for the phono stage, and one small tube--a 12ax7- in my power amps. I’d say any advice regarding a particular tube will be in a vacuum (sorry) given the balance you are trying to strike.
Out of curiosity, do you have another source that doesn’t use the DAC- and did you reach similar conclusions regarding the tubes you’ve tried so far?

So for power I found power supply with some type of toroidal transformer to be cost effective enough, the preamp has a lps, and the people who design my dac went really far and wrote a white paper a few pages and talked about the effort they put to clean the power. 

The issue pretty much goes away with a switch of tubes. I'll try to change sources and see but I'm pretty sure it's the tubes. 

I got some tube recommendation and ill give it a try. 

All things aside, my favorite tube in the 'J8 family is the GE 6dj8 smoked glass. Rich midrange, yet not bloated. I will do tweaks around them to bring out the top end they lack. That's how good I think they are. 

Now don't ask me about the time I was at a surplus place and pulled out a drawer of about 20 Matsushita CV2493 and only bought 2 at the paltry sum of 1 dollar each!   

Good luck on your search.   

I should also note that the dac is aggressive not in tonal qualities but just sheer amount of detail it is able to retrieve. It sounds like hd tv would, you see eveything but it in an artificial way. The tubes blend the sounds together to one coherent sound. If I bypass the tube stage and just dac to amp I don't have the issues.

At this point give Tube World a call and ask them about this,

 " 6DJ8 Amperex Holland 1958-1959 "D" getter halo (the rarest and most sought after 6DJ8, very lifelike sound) (oldest and rarest 6DJ8 Holland in stock) (these are the best 6DJ8 to use in a linestage, more musical than CCa Telefunken) (6DJ8 Holland sound excellent in preamps by AR, CJ, Audible Illusions, Sonic Frontiers, VAC, CAT, etc.) (HEART tube CD player) Customer Comment: ---------------- "All my absolute favorite 6DJ8's are made in Holland. They have the rich midrange that I love."