yoby, hi; that wouldn't be a bad guess, but in this instance it is a different setup. (BTW, on a speaker review underway the Exogal Comet/Ion combo was superb!)
In this particular case the new Cipher Tube DAC from Wells Audio was under review. I just submitted the article for editing and technical check a couple days ago, so the review should appear soon. It's a gorgeous sounding unit, and it plays very well into an amp. My unit did not have the volume control built in, but Wells is working on that. Of course, one has to use software attenuation when using dedicated DAC direct to amp.
I actually discuss the question of Pre/no Pre in the article, because I had varying results with the same DAC and two different preamps. :)