I think my experience might be helpful to this discussion.
I have a Node 2 going into an NAD Masters M12 Pre/DAC - which is a pretty nice DAC. I’ve had some issues with networking via Wifi w/ the Node 2 but that was solved (I hope permanently) by connecting via Ethernet.
Connecting the Node 2 to my DAC was an audio quest digital cable (don’t remember which one but it was about $150 if I remember correctly) via coax to my DAC. I decided to try a Nordost Hymdal digital cable (true 75 ohm BNCs) and asked my wife what she thought. She doesn’t really care about any of this but she clearly heard a difference as did I. Not a night and day difference, but certainly the Nordost cable just offered “more”.
Steve at Empirical Audio, who posts here frequently, can be credited with convincing me that a true 75 ohm digital cable (and most are not) is important. He wrote a white paper on it and I found his arguments logical and they are now backed up by my experience. Cables do matter - even digital - which are transmitting digital information in an analog domain.
Then, to satisfy my own curiosity, I brought my Aurender N100H from another system and inserted it. I connected the Aurender to my DAC via a crystal cable USB cable (USB is the only out on this model Aurender). I started playing the same ripped file on both the Aurender and the Node 2 (the file was stored locally on the Aurender, and the Node 2 played the file (exact same rip) pulled from solid state hard drive on a Mac Mini connected to the network. Certainly this was a more complicated connection, but it’s how I was able to make any comparison.
I was able to switch inputs on my DAC easily to compare the two servers. Of course, the digital cable coming from the Node 2 is vastly more expensive to the USB cable coming from the Aurender, though to be fair, that isn’t a budget cable either. Nevertheless, the Aurender N100 was significantly better than the Node 2. A difference easily discernible by my non audiophile wife.
This difference was true whether playing a ripped file, or streaming via Tidal - which, like the OP, I do at least 75% of the time.
Of course, there is some question about which is ultimately better, USB or Coax. With the equipment I have, I wasn’t able to make that comparison. Based on other discussions, I understand that most believe Coax to be superior which should give the advantage to the Node 2 in this comparison.
While I agree with other posters that the Node 2/2i is a killer device for what it does at the price (and I have 2 of them within my 3 systems), I can say that an outboard DAC yields significant improvements. And, I can say than anyone would easily hear how much better the Aurender is over the Node 2 as a server.
My $.03 (inflation).
mgrif
