Streamers with tube output stage?

Why? You searching for your definition of "tube sound?"

Or just extraneous maintenance?

Gosh. I don’t think this exist…

I know it exists, sort of. Modwright offered a modification of the well regarded Cambridge CXN V2:

https://www.modwright.com/modifications/cambridge-cxn-v2-tube-modification.php

https://forum.audiogon.com/discussions/cambridge-audio-cxnv2-truth-mod-tubes-make-all-the-difference

Problem is, Modwright has discontinued the mod.

I also think noise is why you don't see any streamers with tube stage.   Tubes are vulnerable to RF noise.    

I prefer separate components,  especially something like a streamer which is essentially a computer.   Not that it will get outdated fast, but it will be like this Tab im typing on... at some point it will no longer be supported by firmware.  

@tommylion

I believe you can order a Lampizator DAC with Roon bridge. This means you do need a separate laptop or server to run the Roon Core on your network.

I wonder if anyone would ask here if there's any laptop with tube output stage for music....

That would be fun