Ethernet already has galvanic isolation. I’m repeating that because it seems it doesn’t matter how many people say this others don’t want to believe it. If you don’t want to believe it then you have 2 options:
- Fiber. This can be complicated and get expensive but swapping from wires to glass/plastic between router and endpoint is an option.
- Buy one of the many isolating devices from many different manufacturers out there. The problem with this is… since Ethernet already has galvanic isolation its near impossible for the claims of these devices to be tested. “More galvanic isolation” isn’t a thing. It either is or it isn’t (and ethernet is).
Now, I’m not saying you won’t hear a difference by using one of these devices… and isn’t it about the enjoyment of listening? No matter what we hear coming from the system, if it provides enjoyment it’s a good purchase. So, go forth and experiment. The Uptone etherRegen is popular. The Sonore opticalRendu is popular. The pink-faun you mention is popular. There are “audiophile grade” switches. The list is pretty endless. But again, “more galvanic isolation” isn’t a thing. But your belief that it sounds better is and that’s more important to your enjoyment of your system.
Edit: I want to add that the Allo USBridge Signature is an isolating device. It’s “30+ LDOs on board” and various isolated power rails are there to “isolate” the USB port from any noise or other nasties that would otherwise be carried onto the USB cable. Additionally it’s suggested, and Allo sells, to use a nice linear power supply with the device which further benefits these characteristics of the device. Some have even found running a ground wire, which Allo provides thumb lugs for on their power supplies, between the USBridge and PSU to be of benefit. Is it the best reviewed / tested device on the market? No, not from what I’ve read/watched (but I have nothing to compare it to). Is it a step up from most other, cheaper, solutions? Yes.