MM- Can you provide more detail on what your beginning plan and outcome goal is?  Are you bringing fiber into the house or converting your router output from ethernet to fiber?  I have played around quite a bit on the later.

Thanks guys. I was both hoping and fearing where this leads.

Hereafter- I currently have internet coming in to a router with Ethernet ports. My streamer/DAC has the option for fiber in so I’ve been curious about using it. I’m curious what you have experienced and what SQ changes resulted, good or bad.

Ghostship- this sounds like a worthy endeavor. I am starting where you started and now wondering if I shouldn’t start where you ended after trying some different things. I purchased an MC220L and a pair of transceivers. Waiting to receive them to compare to against my normal connection.

It’s kind of wild to me that shielding and isolation have so much more to do with SQ than bits but it makes sense once you think about it. There’s definitely part of me that is nostalgic for the analog source but the sheer amount of music available digitally and the SQ that digital provides these days is worth the journey.

MM, I am in full agreement with Ghostship in that optical for me on my 2 systems are a definite SQ enhancement.  There are some differences in opinion on other forums where some members feel it just sounds better without optical.  I started out with a basic set up buying 2 FMC’s with an optical cable on Amazon for $70.  Nice improvement…then I added a dual plug Linear Power Supply where both FMC could be clean powered…even better improvement.  I then added an EtherRegan switch with clock which I didn’t hear much improvement and sold it.  Next I upgraded ethernet cables and the one going to the streamer off the second FMC made another noticeable improvement. Recently I added Sonore Opticalmodule Deluxes and wow that was the most significant improvement.  Not cheap but well worth it IMHO. They have a built in clock and other filter goodies.  Highly recommended.

My current system set-ups are:
Main System= Mesh router- Sablon Ethernet Cable-Sonore Opticalmodule Deluxe- Optical Cable-Sonore Signature Rendu SE Deluxe Streamer
Second System= Main Router-Veritas Ethernet Cable-Basic FMC- Optical Cable- Sonore Opticalmodule Deluxe- Veritas Ethernet Cable- Gustard R30 Streamer/DAC.

Learnings/Tips:  
- When using 2 FMCs or a switch and FMC place the highest quality one closest to the streamer.
- Ethernet cables do make a difference.  Place your best quality cables closest to the streamer.
- LPS power supply’s on FMCs and switches make a difference and should not be overlooked. Don’t need to spend big.  I use a dual output Topping P50 sold on Amazon.  
- i added some upgraded Finisar SFP Modules and can’t say I heard an improvement.  
- I tried several ethernet filters like the Stack Smoothlan and determined they weren't needed when I added the opticalmodules.
https://www.smallgreencomputer.com/products/sonore-opticalmodule-deluxe?srsltid=...

Hope this is some added insight into what works for me, my ears on my systems.  Enjoy and best to you on the journey

I checked the manuals for both the MC220L and the Lumin T3x, the active cables I mentioned should work perfectly...although I confess I'm not actually an expert either, lol.

I have the benefit of having essentially a dedicated internet connection to my streamer. The line coming into my home goes straight to a WiFi router with only one network connection going to my streamer. The only WiFi traffic on the router is my phone which is used for telling the streamer what to play.

In my limited understanding of this whole thing I am guessing this is good. I’m hoping using the fiber port on my streamer will provide isolation for whatever is coming out of my router, and if I get a LPS for the magic box that converts the Ethernet to fiber I’ll be addressing another weak link in the chain. But I’m also prepared to be wrong.

That’s a good idea, Hereafter. I’ll see if I can find a seller that will make me a dual output lps that meets the power requirements for both devices.