OP: I don’t know exactly how those two different servers run Roon - it’s possible they’re adding some DSP or otherwise doing non--Roon-standard manipulations. But if not - same Roon version, same configuration, across a network, bit perfect is bit perfect. Doesn’t matter the server source.
For clarity, my post is not about hooking a DAC up to a server directly, where at least there is a form of direct electrical connection. It’s about server streaming to endpoint over a network.
If some of the posters’ suggestions here were true, when you go to an ATM to withdraw cash sometimes you get a few dollars less and sometimes a few dollars more. When you check your bank account online the numbers will be different every time. When you email someone, the network will introduce typos. When you send a word document, text will change.
IP network transmission simply does not work that way. As long as you have bit perfect music input at the server end you’re going to have the same bit perfect output, no matter what else is at the server end, at the streaming end. [Admit the distant possibility of streamers sounding different].
If you want to explore this, I suggest you take a computer and use that as a Roon server to your same endpoint and do those comparisons. As long as you’re not hearing dropouts, and each is configured for identical DSP, volume, etc., whatever processing you have configured is identical (and there’s sufficient horsepower!), it’s gonna sound the same. I have 3 roon servers here on different platforms for different reasons, but it’s not SQ.