What's a really great Streamer/DAC box for just streaming Tidal?

Teac nt505 will beat LUMIN D2 and costs less and uses same control app. Go with modern dac technology not 12 yr old dac technology. Ymmv

@larry5729

(1) If you use optical out of a streamer, you will bypass that streamer’s DAC. You are only using one DAC.

(2) I don’t exactly know which S2 DAC your have, but even if your S2 supports MQA, it may not be decoding MQA. For example the Pre Box S2 Digital supports MQA only over USB, not SPDIF. It's on the Pro Ject website. So, your comparisons between the Node DAC and S2 DAC may actually be comparisons between MQA and CD streams. You may ask your dealer for a refund if your dealer intended to sell you DAC to decode MQA, or if you made it clear to your dealer that you wanted to decode MQA.

larry5729
When you connect the Bluesound Node 2i to another DAC via its optical or coax output it bi-passes the Bluesound DAC and uses the DAC "down the line"

I don't know why I found using just the Bluesound Node 2i to sound better than the external DAC.  Is there something about listening to Master recordings streaming TIDAL's MQA?  I sensed warmth and space for some reason.  Wonder if anyone else hears the difference when streaming MQA or am I trying to believe MQA must be magic?

No one can answer your questions about why you prefer one DAC or streaming source over another.  Make your own decision and enjoy the music.