Lumin X1 Fiber Optic Network Discussions

In Roon forum @Flashman posted his Fosco fiber test results
8275aa37c8abbc755b74c6d3615aaadbacfa1f3c.jpeg

Here's mine from fs.com purchased in 2019. Lower dB values are better.
ac6405e5c03533958ba069efb27b8de91bb9c374.jpeg
 
With routers such as TPlink Deco BE85 offering SFP+ ports, does it make sense to connect these routers directly to Lumin X1 via fiber without the use of a switch or FMC?
 
With routers such as TPlink Deco BE85 offering SFP+ ports, does it make sense to connect these routers directly to Lumin X1 via fiber without the use of a switch or FMC?

In my experience, yes, it is preferable to connect these devices via fiber rather than copper Ethernet (using a switch). This because fiber doesn't transmit low- and high-source leakage current (usually from the SMPS that power Ethernet switches), which causes threshold jitter and results in timing errors.

Per your question regarding connections, AFAIK, you should be able to connect the SFP+ port on the TPlink Deco BE85 directly to an X1 via LC/LC optical fiber. This will still require two FMCs (Fiber Media Convertors), though: one for the "upstream" SFP cage (that would plug into the Deco Be85), and one for the "downstream" SFP cage of the Lumin the X1.

So far, I've found that the Planet Tech TL-40 LC/LC SFP optical transceivers (ref: MGB-TL40 Mini GBIC Single Mode Module, DDM Supported - 40KM provide the best audio performance. These are "single-mode" FMCs, which require the use of single-mode fiber, such as the Corning ClearCurve 9/125 fiber Peter referenced above.

Also, "designed for audio use" Ethernet switches that also have an SFP cages, e.g. the UpTone Audio EtherREGEN, or the SOtM Ethernet switch, or "designed for audio" optical transceivers, e.g. Sonore's OpticalModule Deluxe, in my experience, sound a LOT better than "generic" FMCs (e.g. the el-cheapo TPLink "generic" ones). One reason is they have much better word clocks in them.

Here's my Planet Tech TL-40 FMC plugged into the SFP cage on EtherREGEN, which is the "upstream FMC."
ER-and-SFP.jpg


The Ethernet cable on the right RJ45 port of ER above runs over and connects to the back panel of Alita (my Akasa-cased NUC Roon Core); you can see part of Alita with its RJ45 cable in the lower right of this photo...

iFi-DC-Purifier-Akasa.jpg


The overall fiber network connection from ER and Alita in the RSR (remote server room) over to my Lumin P1 in the main audio rack is shown in this diagram.
Streaming-System-Setup_P1.jpg


Hope this helps, cheers.
 
With routers such as TPlink Deco BE85 offering SFP+ ports, does it make sense to connect these routers directly to Lumin X1 via fiber without the use of a switch or FMC?

It looks like it's going to be much more expensive than getting separate network equipment, and we have not received any compatibility report of using it this way.
 
This paragraph from the 6moons P1 Mini review catches my attention (along with several that mentions competitors but I won’t quote here):
Switching to fibre-optic LAN yielded more refinement than expected over my regular Audioquest Ethernet cable. Since my LHY Audio SW6 switch includes an SFP optical port like the Mini, I purchased a pair of SFP LC modules and 10-meter optical cable as recommended by Lumin to check on any audible differences that may arise from electrically decoupling the Mini from the network. Those turned out to be subtle yet meaningful. Overall the already quiet background got even quieter, small textural detail became more audible and a very fine layer of upper-midrange glare I hadn’t even noticed left. The effect was very similar to what you hear with a high-quality USB noise filter; or to invoke bird-watching as another hobby of mine, switching from very good Nikon binoculars to Svarovskis. The birds are still birds but their colours more vibrant, they look more 3D and it’s a lot easier to differentiate the finest feathers. That’s what switching to optical networking does. If you don’t try it you won’t miss it but once you try and listen in, the differences take the P1 Mini another rung up the refinement ladder. A LHY Audio, a pair of LC modules and 10m cable will set you back about $600. If you already own a decent power cord and pair of interconnects, moving to optical is likely the most meaningful upgrade available for the P1 Mini.

Lumin has native SFP network support on X1 U2 P1 P1MINI.
 
This paragraph from the 6moons P1 Mini review catches my attention (along with several that mentions competitors but I won’t quote here): <SNIP>

Lumin has native SFP network support on X1 U2 P1 P1MINI.

And that is really awesome and most appreciated. In my experience, native SFP network is the best methodology for connecting networked audio devices. Learned this some years from John Swenson, a career EE who worked for Broadcom and Cisco, and who does design consulting for UpTone Audio and is the design engineer for the EtherREGEN.
 
Back
Top