Thread: Lumin X1 Fiber Optic Network Discussions

How did you solve it?

If you mean Roon Core - (RJ45) X1 (SFP) - SFP Switch, yes that'll work. There is a school of thought that prefers a direct network connection between the source (Roon Core) and the endpoint (Lumin) without going through a network switch.

An alternative way is Roon Core (SFP network card) - (SFP) X1 (RJ45) - Switch.

The key thing is that you should not connect Roon Core (a second Ethernet port, if present) to the switch forming a network loop.

For some reason I had totally forgot I have SFP switches scattered around my home - maybe I shouldve sprouted for the X1. 😂

In the Facebook group there is a discussion about whether short fiber can be safely used.

My answer is that with 10km SFP modules, there is negligible concern of damage, according to P.77 and P.78 "Damage by Overpowered Transmitters?" of
https://archive.nanog.org/meetings/n...Optical.39.pdf

All the SFP modules in use by Lumin office have continued to work.

Hypothetically, even if it dies after being used for several years in a consumer audio setup, we are talking SFP modules which cost only $7 - $50.

For more discussions please see networking - Can Fiber optic cables be too short? (dBm too high?) - Server Fault

Most models of unmanaged 1000Mbps SFP (not SFP+) switch should work.

Avoid anything that is managed or labeled as smart. Avoid TP-Link SFP switch as they require a manual configuration. (Inexpensive TP-Link unmanaged non-SFP 1000Mbps switches are fine for Lumin products with conventional RJ45 Ethernet connections.)

I think some users here have used inexpensive Trendnet unmanaged SFP switches with success. At the expensive end, SOtM sNH-10G switch is also known to be work.

Why unmanaged? I have a meraki go, will that not work? To me, sfp>sfp is a standard, cant understand what the switch being manageable or not would make a difference?

Originally Posted by wklie

I am pleased that another major manufacturer has announced a product that also includes optical Ethernet as found from Lumin X1. I think this validates the feature as being valuable and important, and reaffirms Lumin innovation in network audio streaming technology.

That fiber surpasses copper ethernet is no surprise to me, Ive been doing it for years, just using blackbox flexpoint converters. From the first minute I experimented with this I recognized significant improvement in almost every aspect of the music. And I tend to be skeptical about most of what’s sold as tweaks and improvements in audio. (And no, you don’t “burn in” a fiber cable; scientifically that makes no sense). With an X1 arriving this week I’m super excited to eliminate that last bit of short, expensive ethernet cable and finally be 100% fiber from switch to X1.

Originally Posted by jmusica

Why unmanaged? I have a meraki go, will that not work? To me, sfp>sfp is a standard, cant understand what the switch being manageable or not would make a difference?

There are many cases of managed switches causing problems in Roon. Unmanaged switches should usually have the correct required multicast behavior, but with managed switches they tend to behave differently for multicast by default. Some will require manual configuration. Some just won't work.

Originally Posted by MaxH13

Hi Peter,
Is it possible to update the product recommendations necessary for Fibre optic shown on the website?
The Cisco switches shown are now unavailable in the UK and I am unsure whether any Cisco switch with SFP ports would be suitable for connection.
Any help you or others can give in this is welcome as it is a totally baffling subject to me and the best I can do is to ensure that I have suitable components for instillation without trying to understand the long streams of word soups of stuff on Amazon.

Hi MaxH13
As far as I know, the Cisco switch keeps living on despite being mentioned as being discontinued. It's in stock at Currys Business (which is where I bought one for an Audio Show in the UK last year) and there is a 1U version in Ebuyer.

https://business.currys.co.uk/catalo...table/P226629P

EBuyer

Not quite as cheap as they once were (dipped to around £120), but still a good product.
But there are other cheaper (and more compact) solutions around too as Peter mentions.

Although I don't know about specific Trendnet models and we have not tested them anyway, your linked one does have the right specs.

For the (pair of) 1310nm single mode SFP modules and single mode LC-LC duplex Corning fiber, please refer to Lumin web page. We never had any known incompatible 1310m SFP modules - we never received any report claiming a specific SFP module to be incompatible with the X1. Recently a user sent us a D-Link SFP module that he claimed to be not working, but it worked in our test setup.

What switch did you use? The Trendnet in post #265 ?

Good. I think that's functionally equivalent to the compact one on the Lumin web page, whereas you got the regular size version that can be rack mounted.

I’ve been using fiber since I bought my X1, about 9 months. Actually one big reason why I bought an X1 was for fiber (being a geek about it) and I already have Unifi switches around the house…just so happens, I use a USW-8-150W that has SFP downstairs and it hangs off hidden behind the rack, next to the Lumin, plugged into the same conditioner. Anyway, decided to try normal CAT5-in into the X1…and I actually prefer it this way. Sound stage seems to sound bigger, with a better sense of realism between instrument placement and scale… but the biggest impact is to the stage height...I am now looking up all the performers during listening.

The fiber seems to have a different sonic impact too, whether there is more noise isolation or less noise…but there is a cost…it does sound more ‘syrupy’ and some of the sparkle sounds tamed or recessed. But was always displeased with the low sound stage, most of the time my eyes getting pulled down lower than the speaker horns/tweeters where the voices would appear to be coming from. (Think of a low grade ‘V’ shape). I accepted that as some bad reflections happening in the room….

But now thats been cured. Perhaps, my ears prefer distortion or just some extra noise on the top end helping out with the illusion of stage height? It been 2 weeks since and I like it. I feel in a way, liberated, cause now the experience reminds of being closer to performers on a stage and/or physically naturally standing in my room rather than distant seating positions. I no longer perceive the performers as (1) really short people, (2) singing in a squatting position, or (3) me being a ginormous spectator relative to the band lol

Originally Posted by Devg

Amazon.com

We have updated the Lumin web site to list this switch: Trendnet TEG-S51SFP v1.1.

My understanding is that some Lumin X1 users have already been using this switch with no problem reported to us. It is also one of the cheaper choices in this category. At the other end of the price spectrum, there's SOtM switch - we never tested it but some magazine reviews used it with X1 fine.

The previous switch was discontinued and difficult to purchase anyway.

Presence in the list only means we have tested it in our environment and we have not come across any network functional problems in our setup. SQ is not tested.

I use a Cisco Meraki with SFP ports and it works fine.

I switched to the Trendnet you mention after trying a Startech fiber converter that sounded bad. The less expensive Trendnet switch (available on Amazon and elsewhere) works well with these Startech SFP modules and fiber cable I wound up using:
https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Also, though I tried unshielded ethernet cables before converting to fiber, I found that a cable advertised as a 22AWG solid copper CAT8 sounded better wherever I tried one.
https://www.amazon.com/dp/B07VVFC1XZ...roduct_details

I’d appreciate any comments on sound quality from users of Lumin products (specifically X1, P1 and U2) who employ a LAN optical connection (fibre, spelled the British way). I’ve been using multimode fibre from Sonore, as I once owned the company’s original opticalModule (oM) that came configured this way. When I originally set up the Lumin X1’s fibre connection, I used the oM, but have since moved to fibre implementation via an etherRegen switch. The sound quality, by the way, is terrific.

Recently, though, I’ve been intrigued by some online posters who’ve heard a tangible difference between multimode and single-mode fibre, with the latter purportedly having an uptick in SQ. As you probably know, Lumin is agnostic on the topic, saying that both multimode and single-mode will work. Lumin’s website suggests the use of Corning’s ClearCurve single-mode duplex fibre; there is no multimode fibre recommended, so perhaps that is a small clue. The recommended transceivers are StarTech and 10Gtek. Again, as the transceivers need to match the single-mode fibre, perhaps this is another small clue that single-mode might be preferred.

I can’t recall the exact fibre and transceivers with the original oM, other than the fibre was specified as Sonore-branded systemOptique Certified Fibre-Optic Cable.

Peter Lie, Lumin’s firmware lead and a frequent, valuable contributor to this site, has shared that one dealer who tested the LAN optical connection with the X1 preferred single-mode. Peter has encouraged people seeking the best SQ to test one vs. the other. To that end, I’ve ordered Corning ClearCurve fibre and some matching Finisar transceivers (FTLF1318P3BTL) that have been popular among some online posters. (As a side note, Sonore now recommends Finisar transceivers as an upgrade to their second-edition oM, perhaps another small clue!) As the purchases were quite reasonable, I don’t mind letting them sit on the sideline while I ponder this dilemma, with the potential help of Lumin users!

Originally Posted by Puma Cat

When I first got my P1, I was using Tripp-Lite 62.5/125 multi-mode LC/LC fiber with the Finisar FTLF8519P3BL optical transceivers. It sounded great, so you can use multi-mode fiber with the P1 and have it sound truly excellent.

Per Peter's recommendation, I got some Corning Clearcurve 9/125 single-mode LC/LC fiber and I now use that with Planet Tech MGB-TLX 1000Base-LX single mode optical transceivers. The sound did improve, as Peter predicted, I would say it was approximately a 10-20% improvement, if I had to put a number on it.

It was a clear improvement, but not what I would classify as "earth-shaking", though.

What WAS an "earth-shaking" improvement, though, was connecting the P1 to a dedicated Shunyata Altaira SG ground-plane noise-reducing hub. O. M. G.



And, true to the superb manner in which Lumin executes at a really high level, they installed a proper chassis ground-terminal on the back of the P1. The BEST type of connection to an Altaira. 👏 Here's a pic showing an Alpha CGC connected to its ground terminal and to a dedicated zone on Altaira.



I'm also using a second ground cable, connecting the unused S/PDIF port to its own zone on Altaira, and two RCA ground cables, one for each channel, connecting the unused RCA outs, each one also to individual zones, for a total of four ground connections to Altaira.

If you think a P1 sounds superb (and it TRULY DOES), you haven't heard anything until you've heard it connected to an Altaira. WHOA... 🤯

Thanks Puma Cat, I just switched from multimode to single-mode fibre and your findings mirror mine. There’s definitely an increase in SQ but not earth shattering, as the multimode was quite satisfying. I’m only at the beginning of my listening, however, but agree that single-mode is the way to go for best SQ.

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

Originally Posted by kk70

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."

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...



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.


Hope this helps, cheers.

Originally Posted by kk70

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.