a remarkably basic question about Roon

I recently did an A B test between the following 2 setups:  A. Streaming Tidal master tracks through Roon ROCK NUC7 hard wired to ethernet with cat7 cables. The NUC is powered by the stock SMPS. The endpoint is PS Audio Perfect wave Mk II DAC with Bridge II. B. Streaming Tidal Masters from Android app moto z4 via tidal connect over wifi to iFi Zen Stream connected via AudioQuest USB cable to the PS Audio Perfect Wave. The rest of the system includes a highly modified GFA-555 powering Dunlavy SM-1's and a single channel GFA-5500 (modified) powering a Dunlavy SC-S2 sub through active crossover. 

The difference was significant. The B system was by far better. The mid bass tighter and more punchy, the highs crystal clear natural and detailed. The soundstage was more defined. 

I like Roon and it appeals to the DIY in me, but not sure I need it now... I only stream music, so it would seem the added functionality for many is a big part of it. I realize my Roon Core is in need of a clean power supply and fanless case etc., and I could build an optical lan, but would that be better sound than system B? 

@thyname Thanks for your suggestion. I just tried hooking up the NUC directly to the DAC via usb and it streamed 96Khz 24bit, but same result.... I also tried using the iFi Zen Stream as a bridge for Roon via the dial in the back which has a roon setting. Same deal. Only needed to listen to the same song for a few minutes, it was that stark of a difference. My interpretation of these results is that a quality dedicated streamer will be far superior to roon, which is essentially a software attempt at making computer equipment perform high quality audio tasks, which they really are not engineered to do. I may try a noise filter after the SMPS to power the NUC, but my intuition is that the Zen Stream will still blow it away.....

@thyname Yes to both, although you have to turn the switch on the back to roon position to allow it to function as an endpoint. @rsf507 Indeed. @shooter41 Interesting. I'm not a headphone guy and don't have any knowledge of those setups, but I appreciate your input. I offered my subjective reviews based on my observations. To say it is inaccurate is really not in the spirit of us all reaching our collective goal of enjoying the best sound. My point is entirely focused on the source upstream. PS audio is a roon endpoint, and pretty much state of the art. The NUC Rock build is recommended by roon as the best solution short of the nucleus so go figure.... Most likely the PS audio Perfect Strean Mk II DAC Zen Stream combination is just that much better!

@shooter41 Fair enough. I knew that would be a potentially controversial statement and as such I'm hoping to hear some more A B comparisons to broaden the depth of knowledge.