RuneAudio Forum

I may be totally nuts but I think I perfer the sound when I use a usb to ethernet converter to receive music versus the built-in ethernet port. What got me thinking about trying the usb port instead was this post, though a few years old it talks about the ethernet port being quite noisy:

http://www.crazy-audio.com/2013/10/tracking-down-noise-sources-on-a-raspberry-pi/

I had a Cable Matters usb3.0 to ethernet adapter laying around so I decided to try it. Initial impression is that music is smoother. I need to compare more.

FYI, I use my Pi3 and Rune as a renderer on my network. I also use a HifiBerry Digi+ board outputting via coaxial to my Mutec 3+ reclocker.

Here is an explanation by someone far smarter than me that maybe shows why I prefer music through the pi3 usb via the usb to ethernet adapter versus from the ethernet port directly:

The big, big, big issue with noise and Ethernet on the Pi is that the Ethernet transformer center taps are tied to the Raspberry Pi 3.3V plane. It has a ferrite, but that is to keep out noise in the MHz range and up, not in the audio range. In fact, the purpose of the center tap is to shunt common mode noise to the power plane!

I have never looked at the layout closely enough, but if true, this might cause some issues. Not everyone would be able to duplicate the same thing, because if you had a short ethernet cable to a hub or a router on the same circuit ground, then it might not matter. If one the other hand, your ethernet cable leads someplace with noisy grounds, or is more than a few feet long, you could (not necessarily would but could) see/hear a lot more noise.

However, a DAC with its own power supply regulator would be mostly isolated from the problem.

Yes, If you use a USB ethernet adapter for better sound that's an excellent option for better sound quality. I know Cable Matters is a well-reputed brand for USB ethernet cable. You can also see other options here.

Hi tboooe, PeteB, joselee07 & JenniferT,
Here are some measurements of the USB 'noise' on a Pi 3B: http://archimago.blogspot.com/2017/01/m ... s-usb.html
And here are some measurements of the Ethernet ‘noise’ on a Pi 3B: http://archimago.blogspot.com/2016/11/m ... ernet.html
janui