Optical Isolation

I have read many a discussion here on AG regarding digital but, I still need some further clarification on the best way to go.

Looking at the Sonore Optical Rendu, which only seems to be sold through Small Green Computer.  It's advertised as a "network player and network streamer" which makes it sound like I do not need something like a BlueSound Node, an ifi Stream, an Innuos Zen or the equivalent, or do I? 

At present, I have a DAC and only want to stream music. I've had a Roon Nucleus in the past and enjoyed it, but only wish to use Tidal, Qobuz, Spotify or Amazon Music at the point in time.

It sounds like optical isolation is the way to go. I just want a simple, clean & quiet set-up, so any advice on this would greatly be appreciated, thanks!




I have a friend who went the small green computer route.  The other route is an "Audiophile" ethernet switch.  A bit less money and not sure that you'll get better quality from optical. We will see what others post.  Coincidentally I'lm hooking up my EtherRegen switch as soon as I finish this cup of coffee (arrived a few minutes ago).  


First impression very positive.  I'll need to give a bit of time to have more meaningfull thoughts.


Technically coax should be better, since transitions are faster, hence system noise (jagged edges on transitions slopes) does not convert to timing jitter, but coax is prone to reflections on characteristic impedance boundaries (that adds/changes shape of transitions) and transfers digital noise by direct connection of the grounds. It can also create ground loops.  Optical is free of all these problems but transitions are likely 10x slower making system noise to convert to timing jitter easier (noise riding on the signal = jagged edge = variation in time of the threshold point).  If your system is electrically quiet or your DAC has good jitter suppression I would try optical first (that's what I have) - less hassle and cheaper.  Otherwise you need to compare different coax cables.  One with closest impedance match (not necessarily the most expensive one) will sound the best - cleanest (since jitter converts to noise).  Also 1.5m-2m can sound better than 1m (because reflections coming from the end of the cable, if any, will likely miss/be late the edge that started them) 

Any device, like streamer or WiFi receiver (like my Airport Express) should receive just bit perfect data, but can have different quality of electronics to convert this data to music (to add timing) and output it (strong, fast drivers, quiet power supply etc.)  IMHO it is impossible to express it in numbers - you need to listen.

I run the opticalRendu player/ endpoint along with the optical module to get my fiber to optical transition hook up.  A nice set up to clean up the potentially noisy ethernet.  I started with the sonicTransporter I5 as a roon core.  Not sure how to run the rendu without Roon as it is a player only.  I'm very happy with this and the latest 2.0 Roon update was really nice for sound quality upgrade.  Call Andrew Gillis at SGC and can get you the info you need.

@kijanki - Thanks, not sure I understand it all, except the "you need to listen" part. I will heed your advice!

@gkr7007 - I have communicated with Andrew in the past, but not really wishing to go with Roon at this time.

@carlsbad - How's that new switch sounding Jerry? Interesting option.


@navyachts You aren't limited to Roon only if you go with an opticalRendu. Rendus are compatible with any DLNA and UPnP software like Lumin App, Linn, etc. Some of those have Qobuz and Tidal integrations. 

You could go with a Rendu, and always add Roon later if you like. Cheers,


@navyachts Jitter converts to added noise proportional to signal level (no noise without music), detectable only as a loss of clarity.  The best way to compare two streamers, network players or digital cables is to listen, paying attention to clarity of the music.

As sbank stated not stuck with Roon. One thing not often mentioned is running Roon with embedded HQPlayer.


Not sure I'm totally understanding OP, but one needs server with OpticalRendu, OR is only dedicated streamer, also fiber media converter in front of OR required unless one has router/switch with optical out.

@navyachts Well I’ve spent the last 2 days playing with EtherRegen (ER). I had a plumbing issue too so I’ve also spent some time recovering in my listening chair from activities requiring contortionism which gave me some good time to compare configurations.

I have 2 switches, the ER and a generic Netgear switch. I started by running the ER off the router and directly to the streamer and then putting the Netgear switch downstream of ER to service the TV etc. . This put the minimum pieces of equipment in the sound stream but required an 8m ethernet cable downstream of the ER. It sounded very good.

But then I looked at the instructions and what others were doing and it seems the normal install is to put ER downstream of your other switch. So I did that. I put the netgear switch at the router and the ER at the streamer (fed by the same 8m ethernet cable by Audioquest) and then I put a short silver ethernet cable between the ER and the streamer and this gave the best clarity, definition and dynamics. I am super happy with the EtherRegen.


PS.  Just had a funny idea.  What if I replaced the netgear switch with another ER switch, 2 in series. that should really clean things up....I really like over the topism.

@sbank &  @kijanki - Thanks

@carlsbad - Ya, it helps if you read the instructions first...lol                                 If you twin up the ER, let us know the results.

@sns - "Not sure I'm totally understanding" Well, that makes two of us!                  Could you elaborate on this: "One thing not often mentioned is running Roon with embedded HQPlayer" and this "but one needs server with OpticalRendu" 

I would just be listening to say Tidal, be it on a computer or W.H.Y.

Someone needs to write a book on this subject with some good illustrations to boot..


@sns - well, that was easy, thanks! Any thoughts on the EtherRegen switch as carlsbad is trying out, or the coax connection as kijanki is suggesting?

@navyachts I have no experience with etherRegen. This is what I can say in regard to coax. In early days of streaming ran long ethernet cable from ISP modem to router (my internet service inlet in dedicated listening room). I then experimented with moving modem from opposite side of room to router to same side via extending coax cable. Long coax much preferable to long run of ethernet. Shorter runs of ethernet also allows for much less expenditure for better quality ethernet cable.



@sns - OK, thanks. I’ll try what I can and will continue to read yours and other’s posts here to try and gain more knowledge on this subject.

@sns - I was now considering purchasing a ALLO DigiOne Signature music player. What would be the best way to optically isolate this unit? Would an optical Rendu work in this case? Thanks!

@navyachts The Allo would take the place of OpticalRendu, performs same function. Allo uses coax out to dac, OR goes with usb to dac. Optical isolation may or may not be best solution for every situation so don't assume you need OR for quality streaming. OpticalRendu optimal use is as dedicated streamer attached to a music server. Read up on one computer vs two computer streaming setups in order to better understand what OR or any dedicated streamer function is.

I think this honestly gets complicated fast. If you add a couple of Ethernet/Optical converters in the way you also are adding new wall warts, and new sources of noise.

@erik_squires - ah Eric, always the voice of wisdom, couldn't agree more. People go on & on about all this stuff in many threads about streaming. But they all know what they're talking about, buy the majority of us don't. It's all just Greek to me!


I went to order the Etherregen and it is out of stock for a while.  I did find this handy list of other switches.