Sounds like we should just go the whole hog and just become a wholesale access provider and build our own audiophile Internet. Then we can get rid of all that pesky noise once and for all.
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After reading all this I am wondering why it even works at all. The Lumin designer (Peter) did tell me directly to get the yellow fibre cable, he even provided a link to the cable I should buy.
Checking a switch for errors is not something I know how to do, I want plug and play for that reason.
It also has me thinking why should I even change anything, it currently works and sounds great? Could I damage the streamer somehow by using multi-mode cable?
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When I used to do network architecture, we would match the mode of fibre used to the conditions (usually OM for short distance and OS for long, and then match the SFP to the fibre installed.
From what Iâve experienced, if your single mode fibre is going to have problems, itâll be pretty apparent.
If your switch and streamer both support SFPâs, you should be able to swap them out for multi-mode (OM) if you wanted.
Or, you know, if the ones that you have now are working, donât swap them out.
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@NO-QUARTER, unless you think (âfeelâ) the single mode sounds better, I do definitely, no other way for me, having played around with the linn dsm/3 for about a year.
Lumin designed and made your streamer, they should know what they are talking about.
To make thing even more confusing, Linn engineers recommend multi-mode.
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Exactly right. What I would say issues are not always that apparent, unless you you are requiring high bandwidth and not solely using TCP.
It could open up if un checked yet another variable for SSDP multicast failure and streamers becoming undiscoverable from time to time which is the last thing the audiophile needs!
I am curious why the company that @NO-QUARTER mentioned was advocating apparently OS for home network use as their consumers mostly wonât have a clue what they are dealing with and are wanting to simply plug and play.
It sounds like Linn are aligned to our thinking however.
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Now that does make senseâŚ.
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Something to also bare in mind when using OFC is the need to keep the terminations clean using a specific tool designed for the job, ideally one using an impregnated roller.
You should do so every time you unplug and reconnect a fibre as even a tiny amount of contamination can cause link failures and error conditions, many of which will go unnoticed as the transceivers arenât being monitored in any great detail.
Also bare in mind that single mode, even if it sounds better is not designed to be frequently disconnected and reconnected, the fibre end faces are more fragile and sensitive and care is required. Multimode fibre is more robust and forgiving and is designed for patching applications over much shorter distances, as such the connectors are more durable and can tolerate a higher number of reconnects.
Multimode is cheaper and less complex as well as requiring less power to operate.
In my case for my backbone I use 10Gb Multimode transceivers (10GBASE-SR) and OM4 optical cables (LC to LC). The SFPâs are industrial type with higher tolerance components and the fibre is armoured with OFNP jacket.
I use S/FTP solid core CAT6A to my Wi-Fi access points all connected back to 1Gb switch ports. The same switches have pairs of SFP slots for direct connections.
None of my hifi equipment has an optical interface but if it did and I was evaluating optical connections Iâd probably start with similar.
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All looks good with my single-mode SFP:
GigabitEthernet0/8 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is 5835.d945.7c88 (bia 5835.d945.7c88)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 1000Mb/s, link type is auto, media type is 1000BaseLX SFP
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 00:00:01, output hang never
Last clearing of âshow interfaceâ counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 42000 bits/sec, 69 packets/sec
5 minute output rate 4544000 bits/sec, 410 packets/sec
102000 packets input, 8824882 bytes, 0 no buffer
Received 420 broadcasts (404 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 404 multicast, 0 pause input
0 input packets with dribble condition detected
608277 packets output, 849360289 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
And, above all, it sounds best to my ears amongst different types of connections, despite whatever are recommended by the linn engineers?
I guess I like the lumin engineers better!
Are we all subjective? Or victims of expectation bias? 
Donât be afraid to try new things, do experiments. This is what is taught at schools.
PS: Just to give a rough idea what I do for a living (lol) - I am, a postdoc from mit, and one of the countless software engineers who toil day and night working for the big tech firms here in the Silicon Valley, and who are responsible for some of âblack magicâ technology in hires audio and video transmissions that the public are enjoying at the moment.
And I guess I am tired of being talked down by some armchair network theorists here (and I do not mean you @Simon-in-Suffolk or @Mr.M ).
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I agree, it all looks good. Are you using LX transceivers? You have done as I have suggested and validated the link for errors. In my experience, once tested at install it is I likely to change in life. The thing is many wonât know how to do what you have done.
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No, that is my point to prove it, as I said, I am no stranger to this stuff.
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Sure, what transceivers are you using with your OS fibre?
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cisco ones, I canât really remember the model because they are in drawers for a long time.
Iâve also tried some sfp multimode modules from amazon, all works fine if I pair them with the right cables.
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Perhaps you are using CSR transceivers⌠these are Cisco short range single mode transceivers ideal for LAN type applications with OS, but last time I looked not particularly cheap.
Yeah Multimode, with OM, especially OM1 and OM2 is more straightforward⌠and not long range.
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Experimentation with suitable planning and sufficient knowledge can be rewarding and a positive initiative.
The points I tend to highlight are to raise awareness of particular considerations or appropriate pre-requisites, cleaning fibre connectors being one many may overlook certainly relative to copper Ethernet cables which are relatively robust.
Itâs certainly of interest to hear of others experiments and on occasion positive findings. Itâs also interesting to see these usecases and the expectations of the user relative to how the standards process defines the needs of the technology. It reminds me of my previous work on home wiring based on POF, G.hn and MoCA as examples.
Iâm also keen to see what benefits Balanced Single Pair Ethernet could bring to low bandwidth devices like audio streamers, low cost, simple to impliment and with high quality cable design.
Glad to hear in your case the outcome was a positive one!
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I got absent-minded about the details, they all came with the package when I bought my cisco switch new (all paid by my former employer, and they did not want them back)
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letâs leave it at that, I would not go down the rabbit hole now. Will come back when there is time.
Btw, your command is incorrect, it should be âshow interface transceiver detailâ.
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Of course no worries⌠it would be good to share for others who want to use OS fibre in their LAN.
As you had logged into your switch on the above post to get the interface stats, it seemed straightforward to do.
Anyway until next timeâŚ.
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Sure 
Iâm chilling now too having a brandy ⌠enthusiastically trying not to dwell on tomorrowâs challenges
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Without wanting to sound critical, but largely from personal experience I think there are too many variables in your tests, and when you have many options it gets darned confusing.
We have not dissimilar setups in some ways - active speakers powered by NAP 250s (yours DR I think, mine olive) and a NAC 282.
I had been using the NAC 282 powered from one or two olive Hicaps until I got a Supercap DR - Iâm on the fence about this to be honest. The SNAXO 242 has arrived to replace an ancient NAXO and the big itch I have after a few queries is to try the Supercap DR on that rather than th2 282 but Iâd have to get the appropriate Naim or 3rd party Burndy - same for you I suspect as well as how to power the NAC 282 unless the Flatcar would work. Most people whoâve replied suggest the Supercap DR would be better on the SNAXO 242 than the 282 and I somehow think that may be the case, though the Supercap DR was a stepping stone to potentially getting a NAC 252.
My LP12 has had many upgrades but Iâm less and less convinced by vinyl as much as I hate to say that. I think itâs primarily realising that vinyl re-releases are extortionate in price, need space to keep them and may or may not retain value when you can stream from many platforms far more cheaply.
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