That’s the solution I was toying with. I was thinking of an optical connection from the router to the Rossini, except I need two transducers: one from copper to optical near the router and another one from optical to copper at the Rossini. I think the transducer is powered, isn’t it?
In my approach, the optical solution is much more plausible than some hi end cable.
A.
There’s an extensive thread from early this [year] that goes into details on how to go about this. You might find it very useful to go through the full thread;
My feelings exactly! It’s refreshing to have a discussion of a good intellectual standard.
I’ll get my hands on a copy. Thanks for the tip.
That’s tempting. But in the middle of the pandemic …
“little” is relative. Here’s what I mean.
I agree. Testing something as a component of your system, in your listening space, stress free, etc. is preferable to making armchair judgments. But see above. And then there’s of course the question of how much you should trust your own ears. I’m not going to get into that again, though.
Yes the transceiver is powered by the media converter which has the SPF port (or ‘cage’ as it’s sometimes called) into which you slot the transceiver. The optical cable then plugs into the transceiver. Optical cables do come with different connectors, but it’s simplest to use the most common LC type. So with the same type of transceiver with LC sockets at each end, the cable required is LC to LC.
You are right, you place one media converter with its transceiver next to the router and the another next to the streamer - optical cable in-between. Any CAT ethernet cable is fine for connecting-up the media converters. They don’t make an appreciable difference in my experience because the optical link has ensured full isolation.
A less complicated solution that brings exactly the same, that is thanks to the use of optical filtration, can be obtained using Gigafoil V4. The advantage of this solution is one device and only one LPS power supply is needed. I was considering an optical solution in my system, but I was scared off by the amount of additional devices in the case of the Gigafoil filter we have it in one box. Of course, I am not a distributor of devices from the company I am writing about. No distribution in Poland. It is worth trying both solutions and checking their effectiveness in your own system. I am convinced that you only have to trust your own ears. So what if someone else hears the improvement of the sound in auer system, if we cannot hear it, it is negligible for us.
The Gigafoil and Keces was never stable for me. I returned them and went to a ~30ft run of fiber optic cable from my switch to a SGC opticalModule just in front of my Upsampler. Since then rock solid Roon.
It’s true that you end-up with several small boxes, but it’s not too much of a problem squirrelling them away in a cupboard or something - like all network gear. A single box solution seems neat, but I don’t know whether they work as well. I’ve not tried the Gigafoil.
There’s a talented EE called Edison Wong who owns a company called Ediscreation out of Hong Hong. He has a product called a Fibre Box which is a one box optical isolation solution. https://ediscreation.com/product/fiber-box/ I did have a look at this, but the component approach is more flexible and fun if you’re experimenting with options.
I have a very short Gigafoil because it is two weeks. I use a different LPS power supply manufactured by a manufactory in Poland. For two weeks I had no problem playing music. I listen to 3-4 hours a day. No interruptions or missing connections. I even have the impression that before installing Gigafoil, losing the connection and searching for Bartók through DCS Mosaic was more frequent. Now it seems to me that this was not the case. Maybe it was improved by updating MinimSerwer to version 2.1 to which I encourage everyone. The new feature showing recently added songs is very useful.
Regards Robert
Usually, when we deal with more devices, there is a greater chance that something will be buffered. I agree that the possibility of replacing optical converters with other ones gives wider possibilities for experimenting. The optical module and the power supply as well as the optical cable can be replaced. In such a situation, we have a lot of options and each change can have a positive impact on the sound of the entire system. Gigafoil is just an example that there are different optical isolation ideas and different devices that can be used. I used to use Optical Rendu + Optical Module from Sonore. Unfortunately, Optical Rendu software was so underdeveloped that every now and then I had a problem because Roon lost connection with OpticalRendu. Using the USB port is not a good solution for DCS devices with an ethernet port. Change and listen to whether I like such a change.
Regards Robert
Found this today. Seems to be relevant to our discussion. 
I have spent much time and money working to make my system - end to end - as high in SQ and low in noise as I can, testing many switches and cabling in/out from my Roon Nucleus to dCS Vivaldi Upsampler. I have been using the Uptone etherREGEN for a few years with Shunyata Omega Ethernet cables. So far this collection does the best. But in the never ending quest, I’m sure I’ll keep experimenting.
Does an EtherREGEN count as an expensive switch. I recently added it to feed my Rossini and noticed a definite improvement as I’m hearing more higher frequency artifacts and the overall SQ is clearer.
Yup, it is relevant indeed, but maybe to show that this discussion defies science. Let’s see.
Falsifiability. Jim says that he is hearing improvements with the new cable. At the moment, there is no way to falsify this claim. Proving that some measurements, or better still, that ALL measurements known to science are unchanged after swapping cables does not falsify Jim’s claim. This alone opens a deep wound: as Popper would have it, if it’s not falsifiable, it’s not science.
Objectivity. "Evidence for the claim must be evaluated honestly, without bias or self-deception. Huh?
Evidence. “Evidence for a claim must be reliable, comprehensive, and sufficient”. Oh dear.
Replicability. “Evidence for a claim should be able to be repeated”. No way.
That’s why I adopted the (pseudo)Bayesian approach: because Bayesians face the subjectivity dilemma by incorporating subjectivism into probability and making it explicit.
@Zapp, I had a feeling the guide would be written too loosely for your background.
…science as delineated by Popper and his followers. Just a short side note - whether Popper did the advancement of humanity (understood as us human beings, not technology nor the economy) a service with the limits he set for science can at least be doubted. We are collectively still very much troubled by disturbing emotions, violence, and so on and have great advancement potential when it comes to compassion and the like.
You might enjoy ‘The Mind’ edited by Thupten Jinpa with contextual essays by John D. Dunne. It goes among other issues into mental factors, the mind and its objects and inferential reasoning. And within the last mentioned topic it goes through categories of correct evidence. It’s an Eastern perspective…
There are a lot of experts on this forum and I would be very interested in @Anupc 's thoughts on this review, if he would be so kind to provide them:
Well, I can address the technical aspects of that review (and leave the listening impressions parts to the imagination 
)
For starters, the bulk of the technical benefits described in that review revolves around the EtherREGEN’s “ADIM” (Active Differential Isolation Moat) feature, with the circuit board separation, isolation, etc.
The fact is, that exact same thing can be achieved with just a pair of $25 Optical media converters - 100% electrical, galvanic, and, noise isolation - with the added benefit of not having to replace (or add to) any existing Router or Switch at home.
And then there’s a brief mention about “hot-rodding” the EtherREGEN with a 10MHz external clock input.
Well, the EtherREGEN uses the Microchip Gigabit Ethernet Switch chip (KS9897S), which requires a 25MHz clock, not 10MHz. So, that ultra precise external 10MHz clock input (that some folks connect to a multi-$1,000 Rubidium Atomic Clock), has to get multiplied/divided by a $20 Silicon Labs clock generator chip (Si5340B), dramatically negating any supposed “phase-noise reduction” properties of the EtherREGEN 
The reality is, even a $50 Ethernet switch with built-in crystal will reproduce 100% phase-noise-free accurate packets that have zero consequences on music reproduction.
If you look beyond that review, the Uptone folks also wax lyrical about the Ethernet PHY in their white paper. Turns out the EtherREGEN uses a common off-the-shelf discrete Texas Instruments Ethernet PHY chip (DP83869HM) for the SFP and “B” ports, while the “A” ports use the free built-in PHYs on the Microchip. Absolutely nothing out of the ordinary.
Bottom line, everything that that $640 achieves technically, can be had for about $100-150. And if anyone is wondering, yes, I’ve tested and still own an EtherREGEN that remains unused.
Here’s a list of books that might be of interest re the discussion on brains, music, science, and the ever present danger of self-delusion. This is a very short list, as so much has been published on these topics; it’s certainly not meant to be exhaustive or covering all perspectives. All I can say is that I recommend the books. No bullshit here!
— McIntyre, Lee: The Scientific Attitude
— Rauch, Jonathan: The Constitution of Knowledge
— Sunstein, Sibony, Kahneman: Noise
— Gladwell, Malcolm: Blink
— Pinker, Steven: Rationality
— Gaukroger, Stephen: Objectivity
— Sagan, Carl: The Demon-Haunted World
— West, Bergstrom: Calling Bullshit
— Trivers, Robert: The Folly of Fools
— Shermer, Michael: How We Believe
— Gazzaniga, Michael: Who’s in Charge?
— Chabris, Simons: The Invisible Gorilla
— Ramachandran, V.S.: The Tell-Tale Brain
— Shermer, Michael: Why People Believe Weird Things
— Gabriel, Markus: The Limits of Epistemology
Thank you very much for the response and these details @Anupc!
I think you also use Roon (the Nucleus is the core of my system)…
In your opinion, what is the optimal way to connect Roon to Rossini/Vivaldi?
I thought dCS recommended simply:
Roon >> Ethernet, via unshielded Cat5/6
Vivaldi Upsampler (or Rossini DAC) >> Ethernet via unshielded Cat5/6
Done.
Do you have any “upgraded” Ethernet products in your signal/connection path?
@Anupc as always thank you for your explanations and contribution to this forum. I have been following ethernet switch discussions for quite a while both here and on the Naim forum. I have many Naim friends who are using the Chord English Electric switch (rebadged Silent Angel), EtherRegen, and finally the Innuous Phoenix ethernet switch. Several here on the dCS forum are using the Melco S100 switch. Of all of these “solutions looking for a problem” for some reason the Innuos Phoenix seems the most “legitimate” to me.
I continue to read, observe, and tread VERY cautiously as the science and logic behind external “audiophile” switches still fails to encourage me to take the leap. I remember discussions from a while back in the Sonore Optical Rendu link you provided above and have gone back and reviewed it again together with some of the comments above which regard optical connections.
Before purchasing my Rossini I used a Linn Klimax DS (since 2011 - I still own it). Linn have always OFFICIALLY recommended a bog standard NetGear GS108 switch to use with their top of the line Klimax DS (dCS as well does not specify anything fancy). With the introduction this past year of a new range topping Klimax DS Organik model Linn have now included an additional Optical Ethernet connection and have gone as far as publicly stating they believe Optical may offer slightly improved performance over standard Copper ethernet.
While I realize what I am about to ask it personal and may be your own beliefs, do you feel an Optical solution (such as one of the several inexpensive solutions listed above (Trendnet etc)) will provide a “slight” improvement over my current Cisco 2960 > BlueJean CAT6 unshielded > Rossini connection?
Best
Gregg
I wasn’t worried about buffering as such, as switches and media converters don’t buffer the signal. The issue of latency did cross my mind. I think we would want latency to be as low as possible, especially with hi-rez streaming. Maybe that places a limit on the number boxes, but I don’t think I’m anywhere near that.
I view the Optical Rendu as a special purpose device, for those streamers/DACs whose primary input is USB. So not great in a dCS context. The Optical Module on the other hand, is general purpose - a direct upgrade for those ubiquitous generic FMC boxes you can get on Amazon and elsewhere.