Anyone tried fiber into EtherRegen SFP?

Putting a 2nd-hand EtherRegen before my Innuos Zenith Mk3 has probably been the single best upgrade I've made.  Like most others' experiences, the shift away from a digital sound has been palpable.

I'm feeding the ER directly from my Netgear Orbi mesh satellite through a Wireworld Starlight ethernet cable.  I was wondering, however, if anyone has experienced significant gains from feeding the ER with fiber into its SFP port? 

I did assume initially that as the ER is a regenerator the quality of the input shouldn't matter that much.  But as I saw another jump when upgrading the ER's input cable it's set me to wondering about optical.



I use quality silver plated cable into my etherregen.  

Fiber may be good but I feel like people to ignore the need to convert the signal to optical and back to electrical in order to use fiber.  Generally these two converters are basic IT grade and can introduce more noise than you are saving by going optical.

my 2c.  I'm willing to listen to other viewpoints.


That is true and an important point. I use optical as my router is 100+ ft from the ER.  I needed to try and consult with people on several different converters prior to settling.  Difference in SQ was obvious. 

A lot of people are doing this now. Jon Swenson (eR designer) recommended using an FMC in front of the fibre. Which is what the EtherRegen does in reverse order, B > A.

I do this in one of my streamers. Since I do this and fibre I do not care about the crap on the bad side of the eR moat.

Some of the official sound police engineers on A’gon like to say the Swenson is a quake but for me the improvement in sound is real ducky.

BTW - fibre is all I use it it very easy to hear improvements with fibre in my setup. As I said before I have a alot of crap on the bad side of the fibre. The fibre and FMC clean this noise up, so the noise does not get into the DAC. How can I tell? I just replace the fibre for Ethernet and listen.

I am using a WireWorld Platinum 8 from my modem to the etherRegen. I guess just the opposite of what you asked.

From the etherRegen, I am running fiber to my Lumin X1. Way better sounding than with ethernet, I am also using the After Dark clock.


I tried the eR with both my Lumin X1 and Musetec 005 DAC + Sonore OpticalRendu (both fibre solutions).



I am using the opposite sides on the ethereRegen. The ethernet cable goes into the B side. The fiber on the opposite A side.



Many thanks.

I have read that while using the SFP port, it is better not using the other ´´ A ´´

ports for other connections  . Is it true ?

I think that is supposed to be true, however, I have never tried it that way.


In case there's been misunderstanding here, currently I'm doing:

router => RJ45 A-port => RJ45 B-port  =>  Innuos Zenith RJ45

I'm curious about:

router => FMC RJ45  =>  Fiber  =>  ER SFP A-port   => RJ45 B-port  =>  Innuos Zenith RJ45

The Fiber package I have my eye on is from ADOT, which contains an FMC, cable and a pair of SFP adapters:

I have  used it and it makes a difference keeping noise on the dirty end 

the media converter too makes a difference . I use the excellent Linear Tube Audio 

LPS which makes a noticeable improvement to the regen, and comes with a excellent DC cable ,  I should mention a decent power cord like the Pangea sig mk2 is good for a Pc not too expensive.   Little green computer sells respectable LPS power supplies for the router ,and converter Ethernet to fiberoptic 

it all counts is sonics, weak link in the chain . Iuse a combo motorola 8702  which makes a nice improvement , uses the faster docsis  3.1 

We wish to welcome you to Munchkinland! ER with fiber into its SFP port... Yes I did try. With my gear, I found the sound a bit too too sterile and went back to using ethernet cables in/out as that sounded more analog. YMMV.

Per Uptone’s instructions when using SFP the EtherRegen can only have one Ethernet in and the SFP out. I run a room nucleus (powered by the UpTone PSU) so there’s that in need of ethernet too. One in and two out are needed for my setup.

Using an external clock, high quality ethernet cables and an upgraded PSU helps too. Hard wired ethernet.

The Telegartner M12 Switch Gold w/ its PSU is even better than the ER. Is it worth three plus times the cost of the ER (w/ clock and PSU figured in). To me yes.

Alex at UpTone is an excellent guy and will answer any and all questions. Real support from a real person. That’s part of what you’re getting too.


Not sure if this paper has Swensons explanation of why a FMC in front of fibre is a good idea. It could have been in a thread post on some site. However, this paper may aid in understanding in this thread. Some people are posting that this is pseudo-science, but my ears are a believer, at least the eR as an FMC.

UpTone-J.Swenson EtherREGEN 'white paper'.pdf (


Supposed to remove the RF buildup in a long Ethernet run.

Even as little a a foot of it.

@wsrrsw You mention Ethernet in and SFP out.  Unless we're using different terms to describe the same thing, I'm wondering about SFP in (A side) and ethernet out (B side) to streamer

I have a Lumin X1 which has a optical/fiber network input.  So I have a very short run of Ethernet cable from the source to a Sonos Ethernet to Optical converter and then run the fiber optic network cable directly into the Lumin X1 (need an inexpensive plug in adapter).  I can say that this helps the sound … not jaw dropping but cleaner and quieter.  I am not sure what other steamers have optical/fiber network as part of their standard inputs.  For those that don’t, converting from Ethernet to optical then converting back to Ethernet again on the input side seems a bit daft to me.

@chilli42 EtherRegen in reverse order like I use with my X1. The Sonore OpticalModule Deluxe, and a lot of other lower cost FMC’s. But these are not streamers.

I tend to think that the Ethernet input on a DAC is not good as USB. I have not bothered even to listen to the Ethernet on the X1, when fibre is available.

However, the easiest way of getting the Ethernet converted to fibre is getting a network switch which has both Ethernet and Fibre SPF. Such as this one that I have. I paid $125-$150 for this one, It has been jacked up to $400. I have another similar switch in the Livingroom that cost $75. Ubiquiti Networks Networks UniFi Switch 8-Port 150 Watts, White : Electronics



There is a long thread on another site with a lot of talk about using fiber media conversions into streamer. The upgrade results are saying it is one of the biggest bang for the buck improvement you can do. You need two fmc’s run by a linear power supply and the shortest cate8 cable that will work for the final run into streamer. All in it is a little over $100. I am waiting for one more shipment to hook mine up. Secondary benefit if it does nothing for sound improvement it gives you lightning protection for your streamer as a surge can’t go through fiber.

Lots of trade offs both theoretically and in actual listening. I've compared optical and ethernet on both sides of two streamer setups, where first streamer used only as server, SOTM and OpticalRendu used as streamers. Also with only one streamer, in this case optical only in front of streamer. Results have been varied and its difficult to pinpoint the reasons. If one has ethernet ISP there is issue of adding extra unneeded conversion, seems logical there would be trade offs in this case, adding extra equipment to streaming chain is always chance for more noise and jitter to enter chain. Sure, optical blocks noise, but it doesn't eliminate noise creation within any particular optical component. Now if I had optical ISP I'd likely want to stick to full optical chain for same reasons.


So, in listening tests with optical conversion in front of my streamer I preferred ethernet over optical via two generic FMC, both lps powered with quality DC, AC cables into power conditioner or lithium ion battery pack. Optical and ethernet noise floors very similar, optical sound somewhat thinner, less natural. Now, optical POST server, as in two streamer setup, I prefer optical with OpticalRendu vs ethernet with SOTM, also prefer it over my new custom build streamer using it's usb output. Now is purely due to optical or is OpticalRendu simply better streamer than SOTM SMS200 Neo?


So leaving out complications of my two streamer setups, in thinking about  only one streamer, so ethernet vs optical post router to streamer. Comparing fully optimized optical and ethernet is difficult. I already have fully optimized ethernet setup which beats best optical I've tried. Now my idea of what makes up a fully optimized optical path is, two Sonore OpticalModules both lps, good power cords into power conditioning, and then optimized optical transceivers such as Finisar 1475 into each, and don't forget about optical cables which may or may not affect ultimate sound quality. Now I don't know if EtherRegen can even operate with these Finisar receivers, if it can would be good upgrade to try.  I just installed AfterDark Project ClayX Constellation Finisar setup post first streamer last night, this package offers two Finisar 1475 receivers which plug into my OpticalModule and OpticalRendu and upgraded ref quality optical. Based on my research this is likely to be ultimate optical offered at present. This setup with two OpticalModules or perhaps even with generic FMC with removable transceivers could be used in front of one streamer setup.


Bottom line, the above may be hard to follow, but essentially I will be testing if optimizing optical pays off. I've already discovered a single OpticalModule vs generic FMC in front of opticalRendu is superior, this will up my game even more. As mentioned previously two OM with these modules or possibly one OM with etherregen if it will accept Finisar, or to make things even less clear, router with optical OUT capability with one OM, if router can handle Finisar receiver. Not easy to follow, I know.


Based on reports of many these Finisar receivers far superior to stock receivers, I shall find out this week, letting Finisars and cable burn in at present.

I had audible gains putting a Cisco 2960 switch before my Etherregen and using fibre between the 2.

Which SFP modules you use apparently will affect the outcome though,  I've only tried a pair of very cheap 2nd hand cisco ones that are not particularly fast nor particularly long ranged. I can look up what they are if necessary.


I've got a rfi/emi filter on the powerstrip for the cisco and a power cord with a pretty chunky ferrite for it. I have it on black ravioli base and footers too.





@discopants , @sns 

Thanks.  Useful info there.  Regarding the SFP modules, they would be supplied as part of an audiophile fiber kit, so am assuming they're fit for purpose - though this would seem to be a highly subjective area.  As far as I can tell from an email with the ADOT guy, he just tried loads of different modes and modules until it sounded right for him.

True, I have tried previously a very cheap fiber bridge (2 old FMCs from eBay for £11) and it wasn't pleasant.  

However, based on putting better quality ethernet cables in front of the ER I suspect a quality fiber hop may allow the ER to sing a little better.

@lollipopguild Yes. Correct.

I also use the Ubiquiti Networks Networks UniFi Switch 8-Port 150 Watts. I tithe to ubiquity. They make great stuff and their app is easy enough to sort out.

I have the entire ER kit, clock, SFP, etc. PM me if you want. I was going to use in another whole house (so-so) system.

I am using the Finisar transmitter/receiver combo. The set I bought were quite pricey and at the time considered one of the better sounding units. 

Although, I'm not sure if these things do contribute to sound quality.


Issue is if one doesn't have optical input on streamer and optical ISP we're converting ethernet to optical back to ethernet. So consider optimized ethernet> optimized optical> optimized ethernet. This would be something like router or switch (both need optimization via lps, cables etc)> two opticalmodules with Finisar, or possibly Telegartner unit Latik pointed out (lps, cables,etc)> optimized ethernet either before streamer or within streamer, in my case within streamer via JCAT Net XE card. So now we have total optimize network from router through streamer.


Compare to simpler all ethernet setup. Only need in most cases a single ethernet filter, something like Acoustic Network Muon. Will optical/ethernet setup described above be superior to this simpler ethernet setup? Lots of complexity involved in the hybrid setup, also expense. For me it would have to pay off big time to go with this complex, cluttered arrangement. Still, could be worth all the compexity, I'm not that far away from attaining the complex hybrid setup if I went to one streamer setup, would only need to purchase a single OM, have every other piece to make this happen. With two box streamer setup, optimizing both sides of  server  gets really crazy with complexity.


​​​​​​​​I use FMC (ethernet-fiber-ethernet) from ER port B to the streamer and it improves sound.

I tried using the ER SFP input, but it degraded sound in comparison to ER ethernet input in port A.

Here is an issue that puzzled me. I upgraded all SFPs to the Finisar 1324, but the ER wouldn't work with it. The ER works well with the cheapo SFP I bought from Amazon. 

I think the ER prefers the ethernet input. I will next try the FMC (ethernet-fiber-ethernet) method between the ethernet source and the ER.



This is the digital chain that I am using with upgraded Finisar transmitters, sound is clear, detailed. Black backgrounds. All using no ether-regen. Upstream network is clean with quality modem. No Wi-Fi routers in my listening room. 

router => FMC RJ45  =>  Fiber  =>  ER SFP A-port   => RJ45 B-port  =>  Innuos Zenith RJ45

These upgraded transceivers are not guaranteed to work with all optical devices, may be ok to try with cheaper generic FMC, may not want to spend big on optical component only to find the Finisar doesn't work with your equipment. There is AfterDark thread over at audiophilestyle fourm that discusses this compatibility to some extent, John or Alex of Uptone contribute.

@sns I have looked at AfterDark, but for such an audition the overhead of import taxes and possible return are discouraging.  My ADOT kit should arrive in a day or two.

Well, I now have a fibre kit feeding my EtherRegen, and even in the few hours I've had it up and running I can clearly state that the level of detail, texture and musicality have gone up a notch, without impacting the overall warm tone which I have grown to cherish.

After previously adding such things as top-notch ethernet and USB cabling (SOTM and FTA), Innuos Phoenix USB and the EtherRegen, it still amazes me how much more quality I can squeeze out of the DAC's input stream.  Those out there who stick to the "1s and 0s" ideology are just wrong.

I consider the ER the best upgrade I've made to my system.  And despite the fact it's galvanic and a moat (etc etc) I'm still struck that the quality of its input matters greatly.  I'd already seen improvements after previously swapping the input Supra ethernet cable for a Wireworld platinum.  Swapping the Wireworld for a decent fiber bridge just added more.  Saying that however, the FMC is now fed by the same Wireworld. Go figure.

For completeness, I should add that I did try feeding ethernet into the ER's B-port and then feeding fiber from the ER's SFP to the FMC, and then to the streamer by the FMC's ethernet.  Basically:  router => ER => FMC => streamer.  But this didn't work.  The music was brittle and hard; the same reason I'd rejected a pure fiber ethernet stage months ago.

So, my ethernet feed is now:

Netgear Orbi satellite => Wireworld Starlight ethernet => ADOT FMC => Fiber => EtherRegen SFP A-port => EtherRegen B-port => SOtm DCBL-CAT7u => Innuos Zenith Mk3

Hopefully that is now me done.  I have a credit card bill to clear.  And I'll be avoiding reviews of the 2nd gen EtherRegen....

Thanks to all who contributed to this thread.



two further suggestions, if I may: use the Etherregen’s grounding post to run a separate ground wire to a good ground. And use a 10m clock on the Etherregen, even if it is only a cheap one. Both have major additional benefits

Thanks @antigrunge2 

First suggestion already done. Russ Andrews router connected to metre long copper rod stuck in ground

Second, thanks for the advice

I have a full fiber ISP and LAN.  So my ER is used to convert light to copper right before my PS Audio Bridge II.  Works great as a higher-end FMC.

Hi @antigrunge2 

Going back to your clock for EtherRegen advice, can I ask what you're using?

I don't want to spend silly money, and certainly not more than I spent on the ER.  I've noticed a Chinese clock, BG7TBL, seems to be a popular choice.  Do you know if square or sine-wave output is better?


YI use an Antelope Audiophile 10m Rubidium clock, having had the one you mentioned before to try it out. Preferred for the Etherregen is square wave but inly if it not done by cheap conversion in the clock’s output. The advantage is noticeable with the one you mentioned. a bit further upmarjet you get much better quality from LHY or Afterdark