Music from Tidal without Nas

Imagine, I have Roon running or working on a Nuc and have a Tidal subscription and my own music on a Nas.

Question: If the Nas is not turned on then I obviously cannot play music from Nas, but what with added Tidal albums? Can I play them?

AS long as your NAS is not your RoonServer then it should not matter. So, give it a go and see.

At this moment Roon is running on an extarnal ssd drive connected to the Nas, the question was to be sure before i buy a Nuc

I have given it a go and seen.
I have a NUC and a NAS. Music on NAS, Roon on NUC. Both Ethernet wired to router and thence streamer. If NAS is off, everything is still fine with Tidal only.

As an aside, I have Rock on my NUC and it works seamlessly and uncomplicatedly.