Using 2m for SM without attenuators just does not chime with my experiences - from the Cisco SFP Modules Data sheet:
“When shorter distances of single-mode fiber (SMF) are used, it might be necessary to insert an inline optical attenuator in the link to avoid overloading the receiver. A 10-dB inline optical attenuator should be inserted between the fiber-optic cable plant and the receiving port on the SFP at each end of the link whenever the fiber-optic cable span loss is less than 8 dB.”
I think its fair to say for the average non IT savvy consumer using SMF on short distances is a recipe for disaster - I hate to think of the support calls
They are elsewhere, in fact to the point Sonore has a difficult time keeping them in stock. But here, on this forum, any mention of fiber and it often gets slapped down, for no good reason.
For those of you who have Wifi as an option; could you remind me why you are not using it instead of hard wiring? I been on this forum for a year now and all this debating about switches, cables and how to wire a streamer for optimum SQ just seems like it’s going down a rabbit hole.
Well, I’ve always lived on the edge, so I’ll get back to you if anything goes wrong. Everything I’ve read has been the minimum distance for LX is two meters (not ZX which is higher power for much longer distances) and lots of IT engineers on Reddit, etc saying that no attenuators needed for SM LX SFP’s and they have used them for years with no issues at patch lengths. That said, probably best to stick with MMF for new users (which is what Sonore supplies with their modules).
I do think it’s important to clarify the difference between mission critical protocol vs sending some tunes to your hifi. If for some reason an SFP failed nobodies stock trade or life will be lost and nothing will blow up. Anyway, enough of this and back to audiophile switches. It would be interesting if somebody was able to compare an opticalModule bridge vs an etherRegen or EE only.
Yep, though I also found this on the Cisco SFP data sheet, so not sure what’s right and wrong, or maybe we’re reading something different (I saw no mention of needing attenuators except in one specialty case). Feeling pretty confident in how I have it setup and the great sound I’m getting so will leave it at that.
“Table 1 provides cabling specifications for the SFPs that you install in the Gigabit Ethernet port. Note that all SFP ports have LC-type connectors, and the minimum cable distance for all SFPs listed (multimode and single-mode fiber) is 6.5 feet (2 m).”
I think that is right but at that length you would use an attenuator with SMF as defined elsewhere… the parameter given is the minimum fibre loss… and so will depend on fibre cable used and it’s efficiency or loss.
If in doubt log onto the device using the SMF SFP and you can see if it’s stressed or erroring. If not then all is fine…
Yes Naim have confirmed that careful positioning of the aerials is that RF energy radiates outside of the metal box… albeit we are talking minute amounts if RF energy here anyway at very high frequencies/tiny wavelengths. The field strength exponentially decays away from the antenna at a rate determined by the wavelength… wifi has tiny wavelengths.
The RF energy created from the Ethernet interface is a lot lower frequency (from around 31 MHz) and so has a longer and potentially more challenging wavelength, albeit that is not driving a resonant aerial as with wifi.
There are pros and cons here…
To me the big variable with wifi is the frame spacing … which in the absence of WMM with Naim means the rspacing can be quite variable… depending on what else is happening with the radio channel on the access point.
Although on Ethernet Naim also don’t use DSCP, on most consumer switched home networks I would expect a far more consistent frame spacing.
However despite this, this has been mitigated to some extent whilst streaming with the new spooling technique on the current Naim streamers compared to the first gen streamers.
I joined the Naim family by way of a Muso-2 which I’ve had for a year. I am just amazed by the depth of knowledge of the members here. After downsizing from a separates setup, I thought the Muso-2 was just going to be a set it and forget it device. But maybe it’s my instinct to tinker and after reading the forum posts, it got me to mix things up. Here’s what I’ve tried and yes, even with a Muso I can hear SQ differences. First it was wired connection, via power line ethernet, then it was wired via Moca adapters, then I added an optical bridge via a pair of fiber media converters, then I switched out to a Cisco 2960 replacing a TP-Link switch. Then I tried wireless which turned out to be a challenge. With the help of Steve Harris I think I’ve got that worked out. In any case, I can only imagine the amount of gear changing and configuration modifications done by those with more complex systems and more components.
So what did I conclude. I like the wireless. It takes a bit of the edge off the sound that at times to my hearing seems somewhat strident. The pace and rhythm remains intact. The fiber media converters did the same but at too much of a price in pace and rhythm.
Bottom line is that in addition just sitting back and enjoying great music; it’s a hobby too!
I’ve had my share of wifi stability issues with a Muso-2. So I understand that downside. Once those issues were resolved I actually prefer the SQ of wireless in my setup. See my previous post in this thread. No switch, no cables, no converters; just a power line to the Muso.
These issues are totally system dependent, and we all have differing set-ups which affect SQ of an ethernet based system.
My Muso first gen was (is) hopeless via wifi, with continual drop-outs. SQ and stability is however much better with a simple ethernet wired connection to my router/switch.
Not possible to log into the opticalModules that are using them so will just have to wait and see and trust. Not using them in my Cisco switch and wouldn’t, but I also found oM to oM to sound better than the 2960 SFP out to oM (that was with MM). Ultimately will probably end up with one oM straight into an opticaRendu streamer.
Reading elsewhere, I see that some use Etheregen switch, with optical SFP to Sonore module , then ethernet to streamer.
They say having the best sound quality with that connection.
Yes I am looking at the opticalRendu, to possibly connect directly to my Catalyst 3560 for a true optical connection. (I notice Sonore advise against using media converters and then electrical connection to streamer for electrical isolation reasons just like I have done on this forum, because it doesn’t…)
The information seems lacking on the SFP transceivers supported by the Optical Rendu … the text seems all vague and generic… do you know?
I assume any short haul SX type SFP transceiver as they mention only OM1 fibre cable…?