Greg, thanks for the recommendation to put the NAS in the upstairs office to keep it away from the Rossini. Never considered that option. To help remove electrical noise from the 75’ copper Ethernet cable, I think I’m going to try this option from the Small Green Computer, https://www.smallgreencomputer.com/collections/systemoptique/products/opticalmodule?variant=32001196589125.
I’ll let everyone know the results.
Brian …
Looking at the Sonore optical deluxe you should be able to have that right next to your network switch via fiber and then run the 75’ Ethernet off of the Sonore. That would isolate the network noise. I’m planning to add a GigaFoil before my Lumin but the Sonore looks like it could work for me as well.
Related, I switched to Unifi Network equipment (Dream Machine Pro and a 24 port switch; both have optical ports) and I will never go back to anything else. The App interface is great not to mention if you really want to get down in to the weeds (firewalls, etc) you can. I also use PoE Access Points which have created a much more robust WiFi network. I still run Ethernet to all my high BW stuff, especially my Roon and Lumin streamer. Highly recommend UniFi if you’re in the market.
Thanks Matt. Andrew (owner of SGC) confirmed what you mentioned above isolating the electrical noise with the Sonore fiber optic device. He also confirmed Greg’s suggestion of moving the NAS away from the DAC.
I recently upgraded from a Linksys 8 port switch to a UniFi 8 port switch and it did make a noticeable sonic improvement.
Thx, Brian …
Brian, something like the TP-Link Fibre Media Converter will do the exact same job for a tenth the price. Get a pair and you’re all sorted with no loss of quality. 
Anupc, Is there something going on inside the Sonore Optical Module Deluxe (https://www.smallgreencomputer.com/collections/systemoptique/products/opticalmodule?variant=32001196589125) that isn’t going on with the TP-Link Fiber Media Converter? Perhaps some kind of filtering. It’s hard to believe the Sonore device costs 10X more than the TP-Link and is only a media converter.
Thanks,
Brian …
Well Brian, as they say, a picture is worth a 1,000 words;
Top: Sonore’s previous model optical module (non “Deluxe”). Price $395
Bottom: TrendNet Fibre Media converter that provides the same exact function (virtually identical to the TP-Link one). Price $46.99
The TrendNet is better in every single way, from power regulation, to completely discrete Ethernet Magnetics, for basically a tenth the price.
Granted I don’t know what the Sonore “Deluxe” model looks like inside, but based on past experience, I wouldn’t bother
I can completely endorse what @Anupc offers here, because . . . that’s exactly what I did when I first explored fiber optic isolation. What eventuallynturned me off was the multiplicity of boxes and little SPS wall warts [also solvable if that sort of thing worries you]. But it does the same thing, with zero apparent performance differential. If you’re already running fiber from your switch, I think you only need one to make the conversion back to copper for your DAC [but someone please correct me if that is mistaken; I used two originally, because I was not running fiber at first from my switch].
Thanks Greg and Anupc. Anupc, just to confirm that I would need a pair of TrendNet Fibre Media Converters as I’m currently running copper Ethernet cable.
Do the TrendNet media converters gets connected before or after my UniFi 8 port switch? I was surprised that the Sonore devices gets connected after the UniFi switch so it basically means that I’d only be cleaning up the electrical noise fed to a single device, in my case my Rossini. I was told that the player (Rossini) is the only device that needs the electrical noise cleaned up.
@Anupc If I purchase a pair of the Trendnet media coverters, please confirm I also need to purchase duplex fiber optic cable such as this, https://www.amazon.com/Meter-Multimode-Duplex-Fiber-Optic/dp/B004Z9301I?ref=dp_atch_dss_sdp_ce&smid=A27DUHPPTQX1VZ_3
Thanks,
Brian …
Brian, I assume your Rossini is currently connected to one of the Ethernet ports on the Unifi 8 switch?
In which case, if you do want to isolate the Rossini with a fiber connection (whether you really need to is a separate discussion), then yes, you will need a pair of the Trendnets, and a pair of SFPs, like these would do;
And corresponding multi-mode LC-to-LC patch cords like the ones you linked to.
The connection would be;
Unifi <—(Eth)—> TrendNet <—Fibre —> Trendnet <—(Eth)—> Rossini
Thanks Anupc. So the NAS doesn’t need electrical noise isolation from the copper Ethernet cable?
Not in my experience. The NAS itself can be one of the mischievous noisemakers. Again, as @Anupc pointed out, whether any of these “problems” are actually audible is a different topic, but I am not at all sure that trying to “isolate” one’s NAS makes any sense. You can, of course. Just not sure it would have any effect. No doubt someone out there has achieved a “significant” improvement by doing just that, but if your DAC is isolated, it seems to me you’ve done what you “need” to do.
Thanks Anupc. I ordered the Trendnet devices. The Sonore OpticalModuleDeluxe device has an optional linear power supply that increases the price. Do you think the linear power supply makes an audible difference?
Nope, it doesn’t need it. Like @PaleRider says, just at the Rossini will do.
Yes, linear PSUs for the fiber media converters will make a difference, but not in the way you might imagine, say, to produce “better” Ethernet streams. The Ethernet streams will be just fine with the switching PSUs that come bundled with the TrendNets.
Instead, it makes a difference because those switching PSUs will measurably pollute your AC mains. So, don’t plug them nude into the same AC mains line as your Rossini (or you will end up negating any little benefit you get from fiber isolation in the first place! 
).
Whatever PSU you end up using for those media converters, make sure they don’t pollute your AC, or better yet, isolate them on a separate AC line, and use a power conditioner to clean up their noise, and keep them as far away from the Rossini as you can.
When people say “separate AC line” what does this mean specifically?
A different outlet?
A different line from the building’s main input from the grid?
Something else?
I move around a lot and rent — I’m not generally tinkering with the wires in the walls!
(When I have AC that even works it’ll be nice. No power since 7:30am this morning where I live. Hooray for infrastructure investments! :-))
Hey Ben, hope you get power back soon. Anyway, when I say “separate AC circuit,” I usually mean, when possible, plugged into a line that won’t lose power if the other item we are discussing is plugged into a circuit where the relay is tripped. And I echo @Anupc: for many devices, there is nothing wrong with a switching PSU [I know some engineers can make the case they are better than linear for certain purposes]; their problem is feeding noise back into the AC line.
Thanks Anupc. My stereo equipment is on a dedicated AC line with it’s own circuit breaker. I do have an electrical outlet nearby that’s on a different circuit breaker. Are you also saying to keep the PSUs physically away from the Rossini or just make sure they plug into an electrical outlet that is on a different AC circuit than the Rossini? The Melco copper Ethernet cable that goes from the UniFi switch to the Rossini is 8 feet long, so I can keep the PSU and the TrendNet media converters about 8 feet away from the Rossini. If that’s not enough distance, should I get a longer Melco Ethernet cable?
The Melco ethernet cable is designated as Cat7 by the manufacturer. That means it is shielded and not recommended by dCS for use with their products. Save some money and buy an unshielded cable such as Belden Catsnake 5e. I recently changed my Melco cables for this.
Sorry for butting in Anup so I return the rest of Brian’s question to you 
Problem with a shielded end-to-end Ethernet connection is that you can induce ground loops; the problem with a shielded Ethernet cable where the shield is only connected at one end is that the shield effectively turns into an antenna, potentially picking up all manner of RFI.
The twisted-pair Ethernet design is BALANCED, it really doesn’t need a shield as common-mode induced signals are cancelled out!
