To get the best out of Node, you need to use,
1) Ethernet with decent quality LAN cable, like Supra CAT8,
2) External DAC as @hilde45 pointed out,
3) Decent power cord, try Cullen PC with figure 8 IEC,
4) Decent quality Digital Coax cable,
I went through this journey last year of building a digital front end for streaming. Background on all of this is that I’ve mostly avoided digital for 32 years because of the harshness that I hear from a lot of digital music and because I think vinyl has sounded more musical. I got a Pro-ject Stream Box Ultra S2 streamer which I started using via Wi-Fi. My initial DAC was an AQ Dragonfly Red with a 3.5mm to RCA cable to plug it into my main system.
Two tweaks that you might try before returning the Node streamer. My perception is that these changes will improve sound quality no matter what streamer you end up with.
1. Turn off Wi-Fi and use an Ethernet cable: As @lalitk suggested, the most significant improvement that I saw in digital with my initial tweaks was to turn off the Wi-Fi receiver on my Pro-ject streamer and use an Ethernet cable.
I can share one trick for doing this. My audio system is upstairs and my Ethernet port is downstairs. I didn’t really want to run 75 feet of Ethernet cable through my house. So I got a TP-Link RE230 Wi-Fi extender (https://www.tp-link.com/us/home-networking/range-extender/re230/) and used that as a remote Wi-Fi receiver to create an Ethernet access port from which I could run an Ethernet cable to my Pro-ject streamer. Creating an Ethernet access point with that $30 TP-Link Wi-Fi extender has been one of the most significant sound quality tweaks that I found in digital.
2. Try a better sounding Ethernet cable: When going to an Ethernet cable from Wi-Fi, I got two Ethernet cables:
- AmazonBasics Cat 6 - basically just a generic Ethernet cable
- Supra Cat 8 (https://www.ebay.com/itm/402913510909?hash=item5dcf8445fd:g:5UwAAOSwB4NW07FZ) - Well reviewed and pretty inexpensive
These were the improvements that I heard from these changes:
- More presence to voices and instruments which sound more forward and distinct in presentation
- Richer tonality
- Less grain to the sound
- Better resolution due to a lower noise floor (This is audible when comparing a cleaner signal to one that is less clean)
- Easier to follow bass lines
- Pace seems faster due to more clarity and better definition to the leading edge of notes.