Sonore systemOptique

systemOptique is a fiber optic Ethernet interconnection scheme that utilizes a new series of Sonore products with optical transceiver capabilities. Please note that this system was also designed to work seamlessly with the original Rendu series.

Why systemOptique?

  1. Shortly after we launched, the microRendu some customers started using off the shelf fiber optic to Ethernet converters for galvanic isolation. The problem with these products is that they isolate the Rendu from the network, but they don’t isolate the Rendu from their low-quality power supplies and their price point circuits.
  2. Later some customers started connecting their Rendu directly to their music servers via Ethernet. This has some obvious issues because you are connecting the noisiest device on your network to the cleanest device on your network.
  3. Recently, some customers have been tinkering with modifying off the shelf network gear and distributing critical clocks over awire. Adding sensitive oscillators to dirty circuits, distributing low jitter clocks signals over a wiring mess, and interconnecting ground plans across multiple devices is less than an optimal solution.

While the solutions above seemed reasonable on face value we understood that noise can potentially find its way into ANY traditional ethernet cable (regardless of CAT series, copper purity, cable quality, shielding, etc…). systemOptique solves the noise problem by creating an optical solution with infinite galvanic isolation between your music server and your opticalRendu.

So how do I get the WOW factor?
What was needed was a properly engineered system and to that end, we designed some new products for your consideration:

  1. Sonore opiticalRendu - The opticalRendu utilizes an SFP fiber optic transceiver at it’s input to provide 100% galvanic isolation from the network and USB-audio output. The opticalRendu has linear power regulation, CPU circuit design with femto clocking, USB circuit design with femto clocking, and a network circuit design with femto clocking. This unit utilizes SonicOrbiter for it’s operating system so you already know how to use it.
  2. Sonore opticalModule - The opticalModule has an SFP fiber optic transceiver along with an RJ45 connector which can be used to add fiber optic networking to your existing wired network. The circuit design features femto clocking, linear power regulation, external power input.
  3. Sonore Signature Rendu SE - The Sonore Signature Rendu SE will get a new Optical Ethernet Input to USB Audio Output. We will also offer an upgrade path to optical Ethernet input to existing Signature Rendu SE owner.
  4. Sonore (product to be announced) - sorry still working on the details.

All - I want to give some feedback after putting into service the Sonore/SGC starter kit. I currently have the SGC i7 with all upgrades running HQ Player into standard Ethernet input. Needless to say, the sound is very sweet indeed. I recently installed the starter kit SFP optical and switch. I typically don’t get too excited about these things, however, I am here to testify to the total excitement I am feeling over what I am hearing! The overall sound is totally been transformed into a truly live performance. The realism and clarity and placement of the instruments on the stage is truly incredible. .I am truly at a loss for the right words to describe the results of the implementation. I have to be honest, I was on the fence about moving forward with this upgrade, after all, my sound was very good. However, this implementation of the fiber optic kit has truly made me a believer. I will be sending my Signature Rendu SE in to be outfitted with the OpticalModule. If you are wondering if you should move on this upgrade wonder no more do it now it’s that good!!

Sonore thank you for your hard work and dedication to the sound! And coming out with this hardware upgrade. Great price as well! :grinning:



opticalModule is now on sale pre-order only. It’s to soon to set a firm ship date, but we expect to ship the opticalModules in about 2 weeks or sooner if possible.

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Here is a simple diagram depicting the installation steps for systemOptique with an opticalRendu.


1 -> 2 Router connects to an opticalModule via RJ-45 cable.
3 -> 4 opticalModule connects to opticalRendu via fiber optical cable.

I think this is a good idea for people who are not yet in to streaming. I put in an optical bridge. This is easily done with two TPlink media converters, low noise 9v power and some cable, cost me £160. (I used a Cisco switch with SFP rather than a media converter at one end - cost $70.) Sonore says their system is better as it avoids the final ethernet link to your streamer which requires an expensive ethernet cable that is subject to external noise. In my system that final cable cost about $5, is about 0.75m long and I doubt is picking up any noise at all. I’m not even sure ethernet cables are affected by noise, only errors over extremely long distances. I am bothered that a TPlink converter costs about $30 (£25) and the Sonore one is $250. So seems like a nice idea for some, although I suspect streamers are increasingly wireless anyway.

Electrical noise can travel through cables, including Ethernet cables.

Why so bothered? If you don’t like the price, and the value that it brings to the table, then don’t buy it. Very simple

There is a very recent thread here:

about the merits, or lack of any, in audiophile ethernet cabling. The difference with analogue cable, which are specifically for audio, is that digital cabling is universally used elsewhere and there are a lot of internet and telecoms engineers who know a lot about it who all say audiophile cables are complete snake oil.

The marketing for this says:

“Some audiophiles have tried to use copper Ethernet to optical Ethernet transceivers to build an isolated gap between their audio equipment and their router. This works well but the final transceiver has to be connected to the network player using wired Ethernet and noise can be picked up at that point.”

I agree with the “this works well”, but the premise is that it is all ruined by the last 75cm of ethernet cable, so I should buy a new streamer and what appears to be a massively overpriced switch. The question is, is there any merit in the premise that a short $5 ethernet cable is going to make any difference compared to using a standard optical bridge after the router.

I don’t know what to tell you buddy. Try it for yourself. Or don’t

We don’t make TP-Link clones. These units are designed from the ground up in the USA, boards are manufactured in Canada / overseas in small quantities, and are assembled and shipped by hand in the USA. We use boutique parts in our units which are expensive and really don’t compare to mass-produced and cost-reduced units. We designed the opticalModule like we design any other piece of audiophile gear. Support for the opticalModule is email based, forum based and sometimes live person based all from the USA. It simply goes without saying or explanation that these units will be more expensive.

BTW we are also making a RoonReady certified endpoint, called the opticalRendu, with optical input and the opticalModule is a necessary part of that system known as systemOptique. systemOptique certification associates network gear which works nice together and some of the TP-Link gear is compatible and some are not. Early on we knew with all the network gear available out there that having our own compatible fiber media converter would be very beneficial to our customers. In fact, the research into the opticalModule tricked down in to the opticalRendu which is very cool from my perspective. While I perfectly understand that there are lower cost alternative in the market it doesn’t bother me in the least if you use them.

If you read the first line of my post I said that I thought that a system designed for optical connections is a good idea and it’s about time there were units with fibre optic inputs.

I posted because the marketing was disparaging of using an optical bridge, which I did based on a recommendation by a UK audio writer and a quick search shows has been suggested by others, see for example
Basically the idea is to eliminate the noise from your router and it is best to keep the electrical noise down from that point until it gets to your streamer/DAC. I do that by powering the media converter with a 9v battery. There is a short ethernet cable from there to my Roon server that has two low noise internal power supplies and then another $5 short ethernet cable to the streamer/DAC that does the reclocking. The power to the server and streamer/DAC is fed from a Shunyata Venom thing.

With regard to the media converter, why is it necessary to spend more than $30? Does a more expensive unit do the job any better? If so, why? Personally, I have no interest where a product is made and I tend to think mass-produced items are more reliable and cheaper. The best example is the most popular consumer product of all, the mobile phone. In my family they are all made by Huawei.

I am not criticising the product, quite the opposite. I am criticising the marketing. The marketing says it’s the last ethernet cable that makes the whole thing fall down. Frankly, I don’t agree and nor do a lot of telecoms and internet engineers and even the chap from Belden. The email that I received bringing this product to my attention (from smallgreencomputer) started, and I quote:

*Network Audio has always had a problem. *
External noise has a nasty way of entering into our audio experience. Like that loud and boisterous Uncle that you just cannot seem to escape from at a family picnic, we just had to accept his presence. We tried to minimize his presence with expensive high-end Ethernet cables, Ethernet filters and more. However, that Uncle never seems to truly disappear.UNTIL NOW!

Frankly, to me this is rubbish. I’ve been streaming for 10 years and the products have now largely eliminated noise and I have never resorted to “expensive high-end Ethernet cables”. I use these:

I and many others use an optical bridge and some products have them built in.

That said, the more manufacturers that facilitate fibre optic cabling the better.

I agree that, “…optical connections is a good idea and it’s about time there were units with fibre optic inputs.” However, that is just one part of the system and we are trying to address both sides of the system and this is why we are also making the fiber media converter.

From my perspective you want to isolate our Rendu from your router, switches, and computers and not have them on the isolated portion of the system. This way it doesn’t matter what power supply you use on them which saves you money. We are not trying to clean up noisy equipment or spend more money on them. Personally, I only buy ethernet cables that are tested and that come with a report. Here is link to the ethernet cables I buy:

If you want to know why it’s necessary to spend more than $30 bucks you might want to read some information posted by John S. I’ll posts his talks on the subject next.

The marketing guys at Small Green Computer are enthusiastic. These guys have used the equipment and read John’s white papers. They also have a ton of feedback from customers who disagree with you. We are not satisfied with the last 10 years of technology and we choose to do things differently compared to off the shelf gear. How boring would life be if good enough was best.

Here is a wonderful post from John S. on the subject,

" The understanding of “isolation” in digital audio has been my passion for at least 10 years. There is a LOT of misunderstanding on the subject floating around in audio circles. Here is a quick summary of my current understanding and how the current products fit in with this.

There seems to be TWO independent mechanisms involved: leakage current and clock phase noise. Various amounts of these two exist in any system. Different “isolation” technologies out there address one or the other, but very rarely both at the same time. Some technologies that attenuate one actually increase the other. Thus the massively confusing information out there.

Leakage current is a property of power supplies. It is the leakage of AC mains frequency (50/60 Hz) into the DC output. It is usually common mode (ie exists on BOTH the + and - wires at the same time, this makes it a bit difficult to see. There seems to be two different types, one that comes from linear supplies and is fairly easy to block, and an additional type that comes from SMPS and is MUCH harder to block. An SMPS contains BOTH types. They are BOTH line frequency.

Unfortunately in our modern times where essentially all computer equipment is powered by SMPS we have to deal with this situation of both leakage types coming down cables from our computer equipment. There are many devices on the market (I have designed some of them) for both USB and Ethernet, most can deal with the type from linear supplies but only a few can deal with the type from SMPS.

Optical connections (when the power supplies are completely isolated from each other) CAN completely block all forms of leakage, it is extremely effective. Optical takes care of leakage, but does not deal with the second mechanism.

Clock phase noise

Phase noise is a frequency measurement of “jitter”, yes that term that is so completely mis-understood in audio circles that I’m not going to use it. Phase noise is a way to look at the frequency spectrum of jitter, the reason to use it is that there seems to be fairly decent correlation to sound quality. Note this has nothing to do with “pico seconds” or “femto seconds”. Forget those terms, they do not directly have meaning in audio, what matters is the phase noise. Ynfortunately phase noise is shown on a graph, not a single number, so it is much harder to directly compare units. This subject is HUGE and I’m not going to go into any more detail here.

Different oscillators (the infamous “clocks” that get talked about) can have radically different phase noise. The level of phase noise that is very good for digital audio is very difficult to achieve and costs money. The corollary is that the cheap clocks used in most computer equipment (including network equipment) produce phase noise that is very bad for digital audio.

The important thing to understand is that ALL digital signals carry the “fingerprint” of the clock used to produce them. When a signal coming from a box with cheap clocks comes into a box (via Ethernet or USB etc) with a much better clock, the higher level of phase noise carried on the data signal can contaminate the phase noise of the “good” clock in the second box. Exactly how this happens is complicated, I’ve written about this in detail if you want to look it up and see what is going on.

The contamination is not complete, every time the signal gets “reclocked” by a much better clock the resulting signal carries an attenuated version of the first clock layered on top of the fingerprint of the second clock. The word “reclocked” just means the signal is regenerated by a circuit fed a different clock. It may be a better or a worse clock, reclocking doesn’t always make things better!

As an example if you start with an Ethernet signal coming out of a cheap switch, the clock fingerprint is going to be pretty bad. If this goes into a circuit with a VERY good clock, the signal coming out contains a reduced fingerprint from the first clock layered on top of the good clock. If you feed THIS signal into another circuit with a very good clock, the fingerprint from the original clock gets reduced even further. But if you feed this signal into a box with a bad clock, you are back to a signal with a bad fingerprint.

The summary is that stringing together devices with GOOD clocking can dramatically attenuate the results of an upstream bad clock.

The latest devices form Sonore take on BOTH of these mechanisms that effect sound: optical for blocking leakage and multiple reclocking with very good clocks. The optical part should be obvious. A side benefit of the optical circuit is that is completely regenerates the signal with a VERY low phase noise clock, this is a one step reclocking. It attenuates effects from upstream circuits but does not completely get rid of them. This is where the opticalModule comes into play, if you put an opticalModule in the path to the opticalRendu you are adding another reclocking with VERY good clocking. The result is a very large attenuation of upstream effects. It’s not completely zero, but it is close.

The fact that the opticalRendu is a one stage reclocking (which leaves some effects from upstage circuits) is why changing switches etc can still make a difference. Adding an OpticalModule between the switch and opticalRendu reduces that down to vanishingly small differences.

So an optical module by itself adds both leakage elimination and significant clock effects attenuation. TWO optical modules in series give you the two level reclocking .

An opticalRendu still has some significant advantages over say an ultraRendu fed by a single opticalModule, the circuitry inside the opticalRendu has been improved significantly over the ultraRendu. (it uses new parts that did not exist when the ultraRendu was designed). In addition the opticalRendu has the reclocking taking place a couple millimeters away from the processor which cuts out the effects of a couple connectors, transformers and cable. The result is the opticalRendu has some significant advantages.

An opticalModule feeding an ultraRendu does significantly improve it, but not as much as an opticalRendu. So you can start with an opticalModule, then when you can afford it add an opticalRendu, also fed by the opticalModule and get a BIG improvement.

I hope this gives a little clarity to the situation.

John S."


Here is another wonderful post from John S. on the subject,

" All the optical does is block leakage, it doesn’t get rid of clocking issues at all (it can actually make them worse). The fact that it is optical does not automatically apply some universal quantum time scheme that mystically aligns edges perfectly, If you send in a pulse, then another that is 50ns apart, then another at 51ns, then another at 49, that difference gets preserved at the receiver, the optical does not magically force all of them to be exactly 50ns.

The raw data coming out of the optical receiver goes into a chip that rebuilds the Ethernet signal using its own local clock, that is done with flip flops inside the chip, these flop flops behave just like any other flip flops, again no magic here. I was trying to avoid re-iterating what I have said before on this, but it looks like I’m going to have to do it anyway.

So how come this reclocking with a new clock is not perfect? As edges from the input stream go into a circuit each and every one of those edges creates a current pulse on the power and ground network inside the chip and on the board. The timing of that pulse is exactly related to the timing of the input data. The timing of the input data is directly related to the jitter on the clock producing the stream. This noise on the PG network changes the threshold voltage of anything receiving data inside the chip, especially the local clock going into the chip. This means the phase noise spectrum of the data coming in gets overlayed on top of the phase noise spectrum of the local clock. It’s attenuated from what it is in the source box, but it is definitely still there.

THAT is how phase noise gets from one device to the next, EVEN over optical connections.

If you look at this in a system containing all uniformly bad clocks, you don’t particularly see this, since they are all bad to begin with. BUT when you go from a bad to a very good clock you can definitely see this contamination of the really good clock by the overlaying of the bad clock. This is really hard to directly measure because most of the effect is happening inside the flop flop chip itself. You CAN see the effect on the data coming out of the flip flop.

This process happens all the way down the chain, Ethernet to USB, USB into DAC box, and inside the DAC chips themselves, finally winding up on the analog out.

Wherever reclocking is happening, how strong this overlay is depends primarily on the impedance of the power and ground network, both on boards and inside chips. A lower impedance PG network produces lower clock overlay, higher PG impedance give stronger overlay.

This is something that is difficult to find out about a particular chip, the impedance of the PG network is NEVER listed in the data sheets! I have somewhat of an advantage here having spent 33 years in the semiconductor industry, spending a lot of time designing PG networks in chips, I have some insight into which chips look like good candidates for low impedance PG networks.

On a side note, because Ethernet and USB are packet systems the receiving circuit CAN use a completely separate clock, the frequency just has to be close enough to handle the small number of bits in the packet. If it is a little to slow or too fast the difference is made up in the dead time between packets.

To reiterate none of this has ANYTHING to do with accurately reading bits, this is assumed. It IS all about high jitter on network clocks working its way down through reclockings to the DAC chips and hence to audio outs. All the work done on DACs in recent years has cleaned up the signals so dramatically that these effects are getting to be audible in many systems.

John S."

Could you post his thoughts on why it’s necessary to spend $520 on a power cable, and $140 on a PSU cable as well ?

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No one is talking about $520 power cables. These devices we design and build have femto series oscillators and linear regulators. If you are going to buy a unit designed this way you might want to invest in a good power supply. However, if you don’t want to you can buy all our gear without a power supply or in most cases with an inexpensive power supplies. Either way the decision is always yours.

We don’t sell expensive Ethernet cables so he was talking about whatever he was talking about. It has noting to do with us. In fact, I recommend only high quality tested Ethernet cables as noted above.

I’m not embarrassed in the least and I’m very proud of the products we make. We spend a lot of time and money on research, product development, and posts sales support so that we can deliver quality products to our customers. As such, customer feedback on our products is exceptional.


So I have a ultrarendu and want to use the opticalModule with it.
Do I also need to purchase a seperate systemOptique Certified SFP module for the ultrarendu and systemOptique Certified Fiber Optic Cable - 1m.

I already have spare 7v lps.

Not Jesus here, but I think you will need two optical Modules to isolate your ultraRendu. I have the bundle in order for my Innuos ZENith MK3, which consists of: 2 x opticalModules, 2 x SFP Fiber Transceivers, 2 x SGC Linear Power Supplies, 1 x Fiber Optic Cable

It’s on the Sonore website for $791

I’m referring to the bottom diagram.

Do you have optical / fiber coming out of your router / switch? If so, that would work. Just a single oM