How does Roon Sound?
I copuld add my opinion here. I have one. I also have a nose, and a cup of coffee, none of the three are useful to you.
Roon sounds liek the systems its implemented with. As noted, the DAC is #1. A streamer ought to make little difference, but does for a few reasons. First, the software (lik Roon) must run on hardware. Isolating the hardware ground noise from the DAC is one source of improvement. While the USB inputs are often isolated, i have a 3-stage approach to ridding me of noise: 1) my own power supply for Roon; 2) a bridge between Roon and my DAC, and 3) dedicated USB power in my bridge. Note i built my own.
A second "sound thing" is the various processing performed. You can up-sample, or not. You cna choose the type of upsampling. You can choose an MQA first unfold or not. You can set buffer windows. Most of these will in the end be opportunities for improvement,
My experience is that between Tidal and a great DAC, along with just plain solid engineering in the middle (no fancy cables or routers) you deal with 99% of the sound.
In any event, if set up right, it can sound truly great. And the various features, remote capability, multi-room, synch-ing are terrific.
I run Roon on ROCK on a NUC with an LPS that i built. Warning - the NUC is an absolute power hog on turn on, my LPS is HUGE (8A regulated out). Holy carbon footprint batman.
G