Curious to know your streaming and dac set up and the best recommended streamer under $15k

@woots, first let me say that I’m extremely jealous of the difficulties that you find yourself having. The Nagra Tube DAC is a great piece of kit to build a system around. And I would assume that you actually want to hear how good it is without adding too much unnecessary noise in front of it. To that end I’d say keep it simple stupid(KISS) as you possibly can by not throwing a $15K streamer/server into your listening chain without first investigating easier and less expensive alternatives. 
 

 I use a Roon Nucleus with a 15-16v Sbooster LPS plugged into an AQ Niagara power conditioner, while using an Audiowise SRC.DX USB to BNC converter as my Roon endpoint, which is between my Nucleus and my Chord M Scaler. So I’m suggesting putting a better PSU on the Nucleus, and then plugging it right into your Nagra DAC and see what you think. As long as you’re just using the Nucleus as a means to pick your music or explore new stuff, without engaging any of the Roon software filters and DSP functions, then the Nucleus is just a pass through that will let you hear what your DAC can really do. Maybe try an Innous Phoenix USB between the Nucleus and your DAC using the Phoenix as your Roon endpoint. You’ve got lots of options. 
 

I have recently switched to an Innuos Pulse.  I do not need Roon or have ripped/stored files. Combined with the Sense2 app, a superb experience. I would ditch Roon, buy an Innuos Pulsar - reclocked USB into you DAC. Qobuz and native Radio Paradise Lossless = Nirvana. 

@dancarlson10 @adasdad 

Two great responses.  

Originally, I did have my Roon Nucleus+ connected directly to the Nagra Tube Dac.  Roon is plugged directly into a Furman Ultra Linear Power conditioner Elite 20.  Ironically I do have the Audioquest Niagara model 5000 on order to upgrade from the Furman.  When I was tinkering the first thing in my setup was Roon directly connected to the Nagra via a USB connection.  Then I went and added the Lumin T2 and went from the Roon into the the Lumin then into the Nagra.  This actually improved the sound, thus my post seeing if there was something out there that would improve on the Lumin as a streamer connection.  I also eliminated the Roon completely and streamed Qobuz and Tidal directly into the Nagra from the Lumin. and that sounded great as well.  Based on the "tinkering" it does sound better in both instances when I have the Lumin directly connected to the Nagra or said another way the Lumin in front of the Nagra.

For relatively little money, you can try an Sbooster (et. al) external power supply for your T2. Installation is pretty simple, it does require you to cut one wire, IIRC.

Aurender N20 is fantastic