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Ethernet cables for audio - Part C: use of fibre optical cables, SFPs, media convertors, etc


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Let's use this thread to share and discuss ideas, experiments and experiences with fibre.

 

Yes, fibre is not really intended for short distance transmission, but it does provide isolation.  However, that benefit may come at the cost of other nasties due to conversion and power supply noise and regulation.

 

It is worth noting some Audio grade ethernet switches have fibre ports, and Sonore also advocates fibre with Opti rendu and Optical Module (media convertor).

http://sonore.us/opticalModule.html

 

For newbies to this subject, this is one type of fibre cable.

Screenshot_20201023-214933_Chrome.jpg

The cable plugs into a transceiver ...

sfpglcsxmmst.main.jpg

 

And the transceiver plugs into a Small Form-factor Pluggable (SFP) ... 

https://en.m.wikipedia.org/wiki/Small_form-factor_pluggable_transceiver.

Screenshot_20201027-212558_Chrome.jpg

 

The tranceiver needs to match the type of fibre cable and needs to be compatible with the device it is plugging into.

 

Domestic network hardwate typically doesnt have fibre capability.  Enterprise class hardware often does.

 

A Media Convertor is a device that converts between optical and wired ethernet.  Sonore Optical Module is an example of a Media Convertor, but there are many such as this generic one ...

 

Screenshot_20201027-215017_Chrome.jpg

 

Edited by dbastin
added link to Sonore, improved info
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8 hours ago, dbastin said:

Yes, fibre is not really intended for short distance transmission, but it does provide isolation.  However, that benefit may come at the cost of other nasties due to conversion and power supply noise and regulation.

 

Not true - plenty of technical applications using fibre for 1-5m runs. 

 

Conversion has no nasties. PSU maybe. 

 

Again if assuming the data gets there just fine, the only thing affected is timing, whether via PSU or non. Noise along cable a non-issue though. 

 

Most issues with fibre IMHO are at the receive end - timing's as good as what you use to convert back to Ethernet if that's what you've got. Most have an RJ45.

 

Best way is a fibre NIC in a PC/whatever with a well-clocked source at the other end. I'm a few months away from this experiment though will report back when complete.

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7 hours ago, rmpfyf said:

Most issues with fibre IMHO are at the receive end - timing's as good as what you use to convert back to Ethernet if that's what you've got. Most have an RJ45.

And that's probably where most of the PSU noise and jitter nasties emerge.

However I am curious if changes on the upstream end of the optical link make any differences. 

 

In ethernet audio, the strangest things matter.  So my assumption is there is potentially nasties at every link in the chain and the aim is to establish if that is the case and link by link from source moving upstream to reduce the impact of those problems to a tolerable level. 

Edited by dbastin
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Just now, dbastin said:

And that's probably where most of the PSU noise and jitter nasties emerge.

 

Not sure about that but would make for an interesting experiment.

 

If it's reclocking (suspect they are) then slot in a nicer oscillator, make the PSU as genuinely independent as can be, get oscillator power on a nice LDO and Robert is your mother's brother. From a 'clean the stuff upstream' perspective fibre certainly takes care of EMI along the upstream line; you're really just left with timing out. 

 

'Most' of the 'nasties' might emerge there though that's relative to 'how many are left'. 

 

You've got to have a problem/opportunity to be able to fix it.

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9 hours ago, rmpfyf said:

Conversion has no nasties

That may depend upon what you define as “nasties”.  I have two optical converters and an optical cable.  To me there is no question as to whether there is a change with the converters in vs not in.  The important question is whether the noticeable to me change is beneficial or not.  My personnel preference is the converters in.  However, it may be that with the conversions that happen something very small that should be there, is removed from the signal during the conversion processes.  Another person who has heard my converters says that to him the dynamics of the sound is reduced very slightly.  It is not a big deal but interesting to consider. 

John

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1 hour ago, Assisi said:

That may depend upon what you define as “nasties”.  I have two optical converters and an optical cable.  To me there is no question as to whether there is a change with the converters in vs not in.  The important question is whether the noticeable to me change is beneficial or not.  My personnel preference is the converters in.  However, it may be that with the conversions that happen something very small that should be there, is removed from the signal during the conversion processes.  Another person who has heard my converters says that to him the dynamics of the sound is reduced very slightly.  It is not a big deal but interesting to consider. 

 

John

 

There are a few schools of approach here. 

 

We can keep adding/trying towards better results, and note where steps are directionally correct. This isn't bad at all, it's just not accessible for everyone to trailblaze. We're fortunate that you and others continue to share your journeys to these ends accordingly. 

 

Some of the rest of us need to try to pick apart the science/engineering involved to guide choices. 

 

To the latter I'd offer that along the optical cable there's bugger all EMI along the line. 

 

Assuming the conversion works as a gateway with usual NICs then there's a clock in the converter too, and related hardware that affects, ultimately, packet jitter. That's it IMHO. You're not hearing 'optical', you're hearing packet timing. Optical = directionally correct. Compromised timing = directionally incorrect. 

 

Mod your Weiss with an optical NIC and feed it from a 2960's SFP and you'd be closer to seeing what optical can do IMHO :) 

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For those who dont know what a NIC is ...

 

https://en.m.wikipedia.org/wiki/Network_interface_controller

 

I dont know if there is a NIC that can be used outside a computer.

 

I have wondered how to somehow install one of these into an endpoint.

 

https://sonore.us/opticalModule.html

 

Or maybe Sonore or Uptone could make the equivalent of this link but ethernet rather than USB ...

 

https://uptoneaudio.com/products/uspcb-a-b-adapter

 

Edited by dbastin
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13 hours ago, rmpfyf said:

Mod your Weiss with an optical NIC and feed it from a 2960's SFP and you'd be closer to seeing what optical can do IMHO :) 

I will forgo the  pleasure of finding out whether what you suggest in respect of a NIC mod would have a benefit.  There may be a benefits with modifications.  The result that I get from the three 3 Weiss components that are in my system provide for me, a quality outcome without utilising any modifications.

John

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1 hour ago, Assisi said:

I will forgo the  pleasure of finding out whether what you suggest in respect of a NIC mod would have a benefit.  There may be a benefits with modifications.  The result that I get from the three 3 Weiss components that are in my system provide for me, a quality outcome without utilising any modifications.

John

 

John, be imaginative - rather than a call to crack out the soldering iron, I'd tell Weiss they need to up their game with a prototype optical in version of what you have, and that in being a valued customer you'll trial it for them against that which you already have :P 

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1 minute ago, rmpfyf said:

 

John, be imaginative - rather than a call to crack out the soldering iron, I'd tell Weiss they need to up their game with a prototype optical in version of what you have, and that in being a valued customer you'll trial it for them against that which you already have :P 

I like the idea Ric.  I will have a conversation with the Weiss Australian representative who talks with Daniel Weiss regularly.  Weiss for a long time has preferred Firewire to USB ostensibly because of the additional quality.  I do not do Firewire.  I wasn't happy when I first got the Network player and had to use an "I" tablet.  I saw that as crossing to the dark side.

 

John

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  • 2 weeks later...
Posted (edited)

I was reminded of this thread, which got closed, but some good info there ...

 

Oh, and it reminds me of reading about people who sent their Media Convertors to the likes of SOtM to be modified and upgraded, and the variuos imoacts of power supllies and regukators, and DIYers doing the same ... which led me to discover the Sonore Optical Module.

Edited by dbastin
um, tweaks..
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If you are running fibre under 300mt and buying from scratch, then use multimode/850nm, it's cheaper and you won't burn out your optical receiver with high light levels 

 

Single Mode, which is mainly 1310nm which is designed to run Kms is far more expensive and if you don't attenuate it over short distances it will burn out the receiver over time. 

 

Now the question.. Which one sounds better? 

 

you are converting electrical to light then back to electrical, more things to introduce problems if not done correctly. 

 

Fibre is good for speed and noise rejection, in controlled environments as in data centres, most short distance connections 1G and under are still just Cat6 copper 

 

But if you to experiment Fiberstore is a good place to start, some good reading on there too. 

https://www.fs.com/au/

 

Hifi is a funny beast, what shouldn't matter does and you might just stumble across something good

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BTW.. 

 

Don't look into the ends of any fibre gear, it will take out your eye sight over time..

 

Also, cap all ends when not in use. Clean ends with either properly designed cleaners or lint free wipes and some isopropyl alcohol. 

 

Dust will cause packets loss, multimode is less susceptible to dust than single mode but both will be affected 

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Some interesting chat about fibre from page 3 of the Switches Part A thread.

 

One member noted better results with fibre even tho the last libk to streamer isxa filtered SOtM Cat 7.

 

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Some interesting info about use of fibre here

 

 

On 03/03/2020 at 7:09 PM, Hytram said:

Single Mode, which is mainly 1310nm which is designed to run Kms is far more expensive and if you don't attenuate it over short distances it will burn out the receiver over time. 

It would be great if you could explain a little about attenuators.

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22 hours ago, dbastin said:

 

It would be great if you could explain a little about attenuators.

https://community.fs.com/blog/guideline-for-fixed-fiber-optic-attenuator.html

 

https://community.fs.com/blog/basics-of-fiber-optic-attenuator.html

 

some good basic reading there

 

to put it basically

 

singlemode, which 'usually' can be defined by the SFPs being 1310 or 1550nm and the patch leads being yellow its designed for long distances, usually 1km to 100km+

 

to achieved this that have to pump up the laser power and make the receiver more sensitive

over longer distances, the fibre, joints and patches will add attenuation.

 

if the the received level is too low you will get packet loss and errors, to fix that its either a higher power/longer range SFP or fix the fault in the fibre run if thats the cause

 

if the received level is too high, you can shorten the lifespan of the SFP by burnout of the receiver, the articles above say you can also introduce errors into the link, but I have questioned some of our Senior IP Engineers about that and they have never seen it, but we dont do silly things like put in 120km SFP on a 2 mt run
anywho, to fix high recieve levels, you need to attenuate the laser, hence attenuators

how do you work out what attenuator you need?

 

you need 

the receiver sensitivity 

and a power measurement of light received

 

the receiver sensitivity 

this is stated in the datasheet of the SPF

 

and a power measurement of light received

so logging onto the equipment and querying the SFP to  state its receive power

or using a power meter https://www.fs.com/au/c/optical-power-meter-35 to measure the light coming out of the end of the fibre patch lead before it hits the Rx of the SPF

 

using https://www.fs.com/au/products/12622.html which is the FS equivalent of the After Dark Constellation SFP, its transmit power is -9.5dBm and its Receiver Sensitivity is< -23dBm

I would be planning on around 16dBm, so a 7dB attenuator would be needed, one in both directions on a couple meter patch lead

 

 

this is why you use Multimode on short runs, its a LED based light and you don't have these problems 

we use 1000s of SPF in our network and now use only Singlemode and attenuate, because we have the know how to do it and means we can just stock less spares

 

 

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On 11/03/2020 at 10:11 PM, dbastin said:

For interest, After Dark Constellation SFP modules and fibre cable ... 

https://www.adark.co/collections/online-shop-special-on-grand-opening/products/copy-of-uptone-etherregen-femto-switch-pre-order-enjoy-worldwide-free-shipping-tax-free

BTW, the link does not go to a special deal on ER.

 

the SFPs are Cisco CN8ID42AAA GLC-LH-SM 1Gbps 1000Base-LX/LH Single-Mode Fiber 10km 1310nm Duplex LC Connector SFP Transceiver Module

 

the patch lead is a commscope

 

both good industry leading gear... not sure where they got the "audiophile' tag from though

 

2 SFP and a 5mt lead $280 AUD

 

 

here is the Fiberstore equivalent SFP (x2)

https://www.fs.com/au/products/12622.html

and 5mt lead

https://www.fs.com/au/products/68297.html

throw in a couple of attenuators 

https://www.fs.com/au/products/48525.html

 

$53

 

or go the multimode route

2 x https://www.fs.com/au/c/sfp-transceivers-57 

5mt lead https://www.fs.com/au/products/43135.html

 

$38

 

 

just be aware

 

looking at what is on that link, the uptone etherregen switch uses cisco compatible SPFs

 

the other end that your are plugging into (a brand "X" switch) will need a brand "x" compatible SFP

 

 

 

will any of this make things sound better
 

I don't F-ing know

Edited by Hytram
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1 hour ago, Hytram said:

will any of this make things sound better

 

I don't F-ing know

Thank you for your posts on SFPs. I do not know enough and likely will not go down that rabbit hole with my EtherREGEN (which I am happy with). Some people say SFPs sound different; I'll pass on that.

Edited by Snoopy8
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Yeah, I am a fence sitter and would love to explore this part of the Audio world, but simply don't have the time ATM (maybe 14 days isolation might change that... Not me, yet)  

 

But in the mean time, if can help out anyone who wants to experiment and share my knowledge, I am happy to help when I can. 

 

My job in the real world is to build the solid foundations so the experts and weave their magic 

Edited by Hytram
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3 hours ago, Hytram said:

will any of this make things sound better
 

I don't F-ing know

Well, I hope to find out I've not blown $200+ too much.  After Dark use the term audiophile a bit too much however in this case they EMI treat the SFP which I assume gains an improvement. Is that worth $200?  I'll get 2 stock versions of the same SFPs to compare let you know.

 

I may also compare with the Sonore certified SFPs and fibre too.

3 hours ago, Hytram said:

the other end that your are plugging into (a brand "X" switch) will need a brand "x" compatible SFP

Aw dang!  The rabbit hole has yet another tunnel.  I am considering Sonore Optical Module.  Sonore has System Optique certified stuff, the fibre cable and SFPs are multi mode though, and they dont have a Contact Us to ask them for compatibilty info ...

 

4 hours ago, Hytram said:

so a 7dB attenuator would be needed, one in both directions on a couple meter patch lead

If there is one at the end of each direction, the other half of each connector wont reach into the SFP.  So do we assume both attenuators go in the 2 sides of just 1 connector?

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I note the ER review on Audiophile Style (referred to above) states ...

 

I settled on the Startech SFP1000ZXST 1550nm/80km transceivers, with a 2m cable. Since these transceivers are designed for long  distances (note the 80km rating), I used 10dB attenuators, which also improved SQ. This combination was notably better sounding than the (Sonore SyatemOptique) TP-Link transceivers. With this configuration, the oM leapfrogged the The Linear Solution OCXO switch. (upsteeam of ER). The oM added even more dimensionality, more meat on the bone, while also opening up the soundstage.

 

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7 hours ago, dbastin said:

 

I may also compare with the Sonore certified SFPs and fibre too.

Aw dang!  The rabbit hole has yet another tunnel.  I am considering Sonore Optical Module.  Sonore has System Optique certified stuff, the fibre cable and SFPs are multi mode though, and they dont have a Contact Us to ask them for compatibilty info ...

 

Sonore look like they use TP lINk SFPs, nothing special

"systemOptique Certified SFP module" sounds exotic, its marketing speak for  "we plugged it in and it worked"

 

and from https://static.tp-link.com/JetStream - FAQ_Hardware.pdf?configurationId=22931

 

7 Does the Switch Support the Optical Modules of Other Vendors?

Generally, the switch supports the optical modules of other vendors as the TP-Link switches are in accordance with the industrial standard. However, some vendors customize their products for specific purposes and their products may not be compatible with the TP-Link switches. Here you are recommended to choose SFP modules produced by TP-Link, which deliver high speeds while extending your network.

 

 

so I would say any Generic SFP will work in both

https://www.fs.com/au/products/75326.html

 

only the big boys lock their gear down to their own SFPs and there are ways around that

 

7 hours ago, dbastin said:

 

If there is one at the end of each direction, the other half of each connector wont reach into the SFP.  So do we assume both attenuators go in the 2 sides of just 1 connector?

 

 

from

https://community.fs.com/blog/guideline-for-fixed-fiber-optic-attenuator.html

 

How to Use Fixed Fiber Attenuator?

As shown in the figure below, fixed fiber optic attenuators should be always installed at the receiver end of the link (X in the drawing). This is because it's more convenient to test the receiver power before and after attenuation or while adjusting it with your power meter at the receiver, plus any reflectance will be attenuated on its path back to the source.

4.png.e5c6e910e6d16ade88633d6f554b98b8.png

 

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Hmm, it looks like an attenuator will make the connector it is inserted onto a little longer.  And if that is correct, then one of the two  parts of the connector will be longer than the other, and thus will not fit properly into SFP.  Am I missing something?

 

Or maybe installation is not diy?

20200313_125715.jpg

Screenshot_20200313-124752_Chrome.jpg

Screenshot_20200313-125317_Chrome.jpg

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You have to pop the clip off and yes it makes them offside

 

We pop the clip off all the time, you have to when you 'roll the fibres' which means swapping Tx/Rx on the link, usually when multiple leads are in the link. Some people put the clip back on, I leave it off indicating that the patch lead has been rolled.  

 

20200313_201525.thumb.jpg.5bbc0a62f04f7cbafe802e6cf6fc0932.jpg

 

Or if you are just running one patch lead between the 2 SFPs you could just put both at one end.. If will work fine, you just wouldn't do that over Kms, the attenuators are not directional 

 

20200313_201857.thumb.jpg.6c78e6466d94e94255b70f370f9cdea5.jpg

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  • 1 month later...
On 12/03/2020 at 6:38 PM, Hytram said:

using https://www.fs.com/au/products/12622.html which is the FS equivalent of the After Dark Constellation SFP, its transmit power is -9.5dBm and its Receiver Sensitivity is< -23dBm

I would be planning on around 16dBm, so a 7dB attenuator would be needed, one in both directions on a couple meter patch lead

So, its been sometime, but I have received the AfterDark SFPs and fibre.  The fibre is 3m long, the minimum they supply based on 'it sounds best' ... I'll see about that.

 

I intend to also get the following to compare SQ:

  • 2 x Cisco stock version of the Afterdark SFP
  • 2 x Startech SFP1000ZXST 1550nm/80km transceivers (as per Audiophile Style review of ER)
  • 1m fibre to compare 1m to 3m.
  • about 8m fibre

My network will be ...

  • Ubiquiti EdgeRouter X SFP > 8m fibre > Ubiquiti EdgeSwith 10X > fibre (1 or 3m) > ER

Incidentally, the EdgeSwitch has HT/TV using it, so I want to isolate it from Router and ER.

 

So I need to know what attenuators I need for 1m, 3m, and 8m fibre cables with the above SFP modules.  I'll also need to find out if the SFPs are compatible with the Edge and ER.  Is there anything else I need to know or get to complete this?

 

I'll try the SFPs in different locations, and keep the best performing pair in their respective best locations.  I can only compare 1 and 3m fibre from switch to ER, which is likely to be the critical/most audible leg.  But I can compare the 8m fibre to 8m of Cat 5e, and maybe Cat 8 if I can be bothered.

 

Somewhere in this experiment I may try a Sonore OpticalModule (OM) here ...

  • Ubiquiti EdgeRouter X SFP > 8m fibre > Ubiquiti EdgeSwith 10X > ethernet cable > OM > fibre (1 or 3m) > ER

When that's all settled, just for kicks, I will compare the best fibre combo with my best Uber Ethernet cable from Switch to ER - I have 3 different cables around the US$1000 rrp mark, and a very revealing system (Antipodes, Devialet Pro, Dynaudio C1, and Shunyata and Synergistic Research power conditioning and cabling).

 

Of course, I'll also post my observations.

 

However I just need a little help with determining attenuator values and SFP compatibility,with Edge Router and Switch, and very much would appreciate whatever heIp can get.

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  • 1 month later...

 

 

1) "fibre is not really intended for short distance transmission"

 

Don't forget about Toslink, been around 30 years, uses short Optical cables.

 

2) along the optical cable there's bugger all EMI along the line.

 

Optical Cables are made of glass ( or plastic) which are insulators. The only thing to travel down the cable is light and nothing else.

 

4) If it's reclocking (suspect they are) then slot in a nicer oscillator

 

The devices / networks we are talking about are Asynchronously connected. Therefore the source has it's own clock and the destination has it's own clock, and the two clocks have nothing to do with each other. The receiver has a challenge because the incoming signal will be completely out of step with what is happening on the inside of the device.

 

When the data comes into the receiver, it's job is to try and decode the incoming stream. To do this it has to dynamically adapt to the incoming stream. The receiver measures the incoming signal ( Light / No Light) and the middle of the width of the bit pulse, where the signal is nice and stable.  A receiver does not sample the signal at the transition / rising edge as this is way way too unstable and it risks bit flip ( clocks are the opposite they are all about edge transitions and hence very susceptible to jitter). Once the Ethernet frame is read in serially, it is put into some type or memory. On transmission it will be read out of memory and clocked onto the outgoing port.

 

So no super accurate clock in the Optical Transceiver module. And all Ethernet frames are re-clocked through Ethernet switches, otherwise you could not have for example a 10G Ethernet network connecting to a 1 G Ethernet network.

 

 

 

 

 

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Hi guys,

I want to ask benefits of high end music serverS if we use fiber optic in between.

 

the main goal of Ethernet streaming tweak is to stop leakage current from upstream and providing clean signal With good clocking system to Streamer ethernet port. This goal can be achieved with Etherregen or optical Module as media converter with high quality LPS or Sonore lifted this game by implementing fiber sfp on the streamer themselves. So why users still report sound improvement by ethernet cable upgrade on router end or people still spend big bucks on audiophile servers. Upstream noise is no longer an issue with fiber in between for 100% galvanic isolation and only fiber converter itself is matter
 

I also curious how noisy optic SFPs are verus normal ethernet, they are definitely more noisy than ethernet port as i found they run super hot and there must a lot of computing power happens inside the sfp to covert light wave to electronic signal

 

those make me curious,

 

thanks for your reading,

Edited by ikhuong
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1 hour ago, ikhuong said:

Upstream noise is no longer an issue with fiber in between for 100% galvanic isolation and only fiber converter itself is matter.

 

FWIW, Ethernet also has galvanic isolation, it uses transformers at both ends.

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38 minutes ago, Steffen said:

 

FWIW, Ethernet also has galvanic isolation, it uses transformers at both ends.

Ethernet isolator was not designed to resolve leakage current 

 

 

 

“Leakage current is a property of power supplies. In all power supplies a small amount of current will flow from the AC line, through the power supply, to the DC output. That current will pass to whatever device is being powered, and will always flow back through some path to the AC line, forming a “leakage loop.”
Such leakage will frequently flow into the ground-plane of a device, generating a small voltage on the ground-plane. This leakage current is primarily at line frequency—50Hz or 60Hz, depending on the specific country’s AC mains standard—though there can be low-level components of it extending up into the megahertz range. Note that this is NOT DC, it is primarily line frequency AC, and that is very important to remember when thinking about leakage loops.
Leakage current can flow through power cables, audio interconnects, digital cables, including Ethernet and USB cables. The leakage will flow from a power supply, through a cable to another device or component, then through that device or component’s respective power supply back to the AC mains. Alternatively it can flow through a cable to another box and then through a safety ground (the “third pin” of an AC plug) and return back to the AC mains.

 

We have found there are two types of leakage current, traditional low-source-impedance leakage, which is found in all power supplies, and high-source-impedance leakage, which only occurs in switching-mode supplies. This high-source-impedance leakage is hard to block and can take surprising paths to get where it wants to go.
These two different forms of leakage currents have a deleterious effect on Ethernet in audio systems. All copper Ethernet connections have transformers in each device port, and these transformers will block DC and low-source-impedance leakage. However, they DO NOT block high-source-impedance AC leakage. This is particularly important for digital networks used for audio.
Most all network systems used with audio use switching supplies (SMPS) to power the digital devices, routers, switches, computers, etc. The high-source-impedance leakage current from the SMPS will travel through the network equipment, the Ethernet cables, the end-points, and into the DAC where they will create noise on the ground-plane, and thus jitter in the DAC circuitry.
Leakage currents can also cause clock modulation in intermediate devices such as “streamers.” The clock issues were discussed in the prior section.

 


UpTone-J.Swenson_EtherREGEN_white_paper.

 

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10 minutes ago, ikhuong said:

All copper Ethernet connections have transformers in each device port, and these transformers will block DC and low-source-impedance leakage. However, they DO NOT block high-source-impedance AC leakage. This is particularly important for digital networks used for audio.
 

 

Yes, I know, all kinds of transducers can pass parasitic signals and noise, including optical ones. I was just referring to the “100% galvanic isolation” feature you put forward.

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Probably worth mentioning that 'galvanic isolation' in the case of a transformer, means that an electrical connection is isolated, and does not mean isolation from noise. A transformer will merely attenuate noise and high frequency RFI is likely to sail right through a transformer.

 

Edited by HumanMedia
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Just now, HumanMedia said:

 

Probably worth mentioning that 'galvanic isolation' in the case of a transformer, means that an electrical connection is isolated, and does not mean isolation from noise. A transformer will merely attenuate noise and high frequency RFI is likely to sail right through a transformer.

 

Yes, just like though an opto-coupler, limited only by the bandwidth of either device.

 

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  • 2 weeks later...

Some food for thought.

I recently came across this review of a Melco/DELA/Buffalo media convertor. 

https://online.stereosound.co.jp/_ct/17383539

https://www.dela-audio.com/product/op-s100/

 

Its in Japanese, which I have translated below, but some is still a bit odd.  The images may be out of order, but simple show the shaded area being where the optical link is in each scenario.

 

 

AV fans also pay attention to the optical LAN connection!

"DELA OP-S100" for clear image quality/sound quality improvement

 

What is DELA's set of options for optical LAN connectivity?

 

One of the sound quality improvement means that has been attracting attention in recent network audio, there is an optical LAN connection. Instead of a normal LAN cable, it is a method of using a cable using optical fiber as a conductor.

 

In the wake of the introduction of Lumin's network player X1, which supports optical LAN connections, I connected optical LANs between routers, hubs, and network players on the second floor of my home. As I tried and found out, the optical LAN connection is slightly more difficult to standard, and it takes time and effort to introduce such as cable is made up of multiple parts. (The detailed reason will be described later).

 

Therefore, I would like to pay attention to the option set OP-S100 for optical LAN connection released from DELA. DELA is a manufacturer that releases music libraries N1/N10/N100 that can be used as network transport/high-quality NAS, high-quality disk drives, network switches, etc. This set consists of three points: an optical media converter that converts normal LAN wiring to optical wiring, an optical fiber cable corresponding to multi-mode, and an SFP optical transceiver that is inserted into an SFP port equipped with an optical compatible device, and the LAN network network can be converted into optical LAN by combining it with a network switch (hereafter called a hub) S100 or BS-GS2016/A that supports optical LAN connections on sale from the company.

 

Optical LAN Adapter Set

DELA OP-S100

62,000 yen (3m set) + tax

 

Media Converters

Converter for converting optical network cables using LAN (RJ45) and SFP terminals. In this set, Buffalo (BMC-GT-M550M / JPY 24,800+ tax, including 1 SFP transceiver) is included. One SFP transceiver is included.

 

Fiber optic cable

Fiber optic cable that allows high-speed/stable long-distance transmission in light conditions. By performing electrical / optical conversion, it is also said that there is also an effect of blocking the influence of noise. There are various standards, but the OP-S100 sets a cable with the specification "multi-mode LC-LC2 core 50/125 [mu] m". Corning's high-reliability cable.

 

SFP Transceiver

Small Form Factor Pluggable (SFP) is a terminal that meets a variety of standards and connects fiber optic cables through parts called "SFP transceivers." Also known as an "SFP module". The OP-S100 is a set of buffalo 1GbpS-compatible high-trust products (BS-SFP-GSR/ Same specifications as optical media converter accessories

 

Lineup: There are various sets from 0.5m set (60,000 + tax) to 50m set (82,000 + tax) in the difference in the length of the fiber optic cable

 

Network Switch

DELA S100

138,000 yen + tax

 

Connection terminal: LAN 9 system (100Mbps compatible RJ45×4, 1,000Mbps compatible RJ45×4, 1,000Mbps compatible SFP×2 [one system of RJ45 and SFP shared])

Dimensions / mass: W215× H61 × D270mm / about 2.5kg

 

DELA, which continues to create high-quality music servers, released the S100 audio component last year with switching hub capabilities that are essential for network playback. It has been well received, but as an option, the optical network adapter set OP-S100 was released. This time, we explored performance from both audio and AV.

 

This time, I would like to use this OP-S100 to verify the effect of optical LAN connection in both audio and video streaming environments, and report on the surprising results.

 

To explain the advantages of optical LAN connection again, the main advantage is to realize high speed of data transmission speed and long-distance transmission of up to about 15km. The optical LAN connection audio, when used in audio-visual applications, it is possible to block the electromagnetic wave noise or the like from the outside that enters the differential transmission noise and LAN cable generated from the LAN circuit around the connected device in principle.

 

However, as mentioned earlier, the introduction of an optical LAN environment is not easy. The main reason is that there are two types of connection methods of single mode and multi-mode (see column below for details), further the optical connection is made up of two parts of the optical fiber cable and SFP transceiver, because it can not be transmitted without properly combining those parts. In addition, there is a difference in shape in the connector of the fiber optic cable tip. In other words, it is difficult to know which product to choose. Therefore, OP-S100 where the above parts are set in advance is beneficial.

 

In addition, the set includes a buffalo optical media converter and an SFP optical transceiver, Corning, Inc., which has a high reputation for fiber optic cables, and reliable equipment, and it is also a good to be able to select from 10 types of cable lengths from 0.5 m to 50 m.

 

 

What are the two modes of optical LAN connection?

 

There are two common optical LAN standards: single mode and multi-mode. Both of the two modes are available for audio or AV applications, but it is important to note that these modes are not different from the protocol (communication method) of the transfer. Both fiber optics have a diameter of 125 .mu.m (microns/1 micron is 0.001 mm), but the cores that transmit signals are 9 or 12 .mu.m in single mode and 62.5 or 50 .mu.m in multi-mode.

 

The two modes have different transmission characteristics and different uses. The single mode is resistanle to long-distance transmission (typically about 1.5 km), but on the other hand, it is weak in bending cables and is mainly used for outdoor wiring. Multi-mode, on the other hand, transmission distance is approximately 500m, it is used in indoor LAN wiring because it is strong in the bending of the cable. SFP transceivers (also known as SFP modules) and fiber optic cables are dedicated to single-mode and multi-mode, and cannot be mixed.

 

Test the effect of optical LAN connection with two types of network players

 

This time, we performed two kinds of tests in the audio environment. One is a Lynn network player, using the climax DSM, assuming the case of introducing an optical LAN connection to a general network environment (connection pattern (1)) The other was also performed pure sound quality comparison of optical LAN connection and normal LAN connection (connection pattern (2)) using Lumin X1 with SFP port corresponding to optical LAN connection from the beginning.

 

Test1 (number)

What is the effect of using phosphorus KLIMAX DSM with an optical connection adapter?

 

Two models were used as representatives of network audio playback: Phosphorus and Lumin. Lynn prepared the highest-end KLIMAX DSM). LAN terminals are equipped with one common RJ45 type

 

DELA S100 Optical LAN

Connection Pattern (1)

 

The router and S100 were compared with (1) a state directly connected by a general LAN cable (copper material cable of RJ45 terminal) (router →S100→ phosphorus), and (2) an optical LAN connection with OP-S100 (router→ optical adapter→ optical cable →S100→ phosphorus / connection diagram).

 

Climax DSM of the pattern (1), first router, hub, after connecting between the network player with a normal LAN cable, was compared by optical LAN in the form of sandwiching the optical media converter between the router and the hub. Lynn's most advanced model, which has received the highest reputation as a network player, has excellent sound quality even with a typical LAN connection. The Vienna Philharmonic "March of the Empire," conducted by John Williams, heard on the streaming service TIDAL (not serviced in Japan), spreads in front of you with a vast sound stage with dense sounds packed in information. Hi-Res File's The Weekend "Binding Lights" also draws a sharp sound image in the center of the left and right speakers with a rich performance with a sense of scale.

 

Next, I tried to connect this to an optical LAN, but it was much higher than I expected. First of all, the noise floor is lowered in a wide range from the high to the low range. As a result, the sound of the small level such as the hole tone which influences the spatial expression becomes clear, and the expressive power of the depth and height direction of the stage increases. The sharper sound representation of "Blinding Lights" has its tongue wrapped around it. I did not feel the disadvantage of the conversion of changing the electrical signal of the LAN connection to light.

 

Also, my experience with many network players was that Lynn's network players were relatively difficult to influence the sound quality of peripheral network environments such as hubs and routers, but it was interesting that even Lynn's players had a clear sound quality improvement effect.

 

If that's the case, there's a lot of expectation for auditioning on the Lumin X1 with the SFP port. Products such as this unit that supports optical LAN connections can be connected by installing an S100 with a regular LAN cable and an optical LAN (SFP) terminal, and adding a compatible module/cable. As with the earlier verification, I first heard it on a normal LAN connection and then switched to optical connection. (Connection pattern (2)) In the same way, in the impression that noise floor and SN ratio improvement on the sense of hearing is common, the goodness of the X1 with a certain skeleton of the mid-low range is further enhanced. In addition, I wonder if this product is tuning by optical connection from the development stage, rather than the dramatic change felt by phosphorus, all bands will be more seamless and gap-free representation.

 

 

Test2 (number)

What is the effect when the Lumin X1 is connected directly to the optical LAN cable?

 

The Lumin X1 is the company's highest network audio player, and Hindoudo has also introduced it. In addition to the typical RJ45 terminal, it has an SFP port that can be connected directly by an optical network cable.

 

DELA S100 Optical LAN

Connection Pattern (2)

 

The Lumin X1 compares a 1LAN connection (router →S100→rumin) to a state connected to the S100 with an optical fiber cable connecting the SFP transceiver attached to the OP-S100 to both ends on a 2SFP port (router→S100→ optical cable →rumin/connection diagram).

 

 

The optical LAN connection also had an amazing effect on AV playback.

 

It is an optical LAN connection that has had a big effect on network audio, but what kind of change will occur when used in a video environment? I challenge the test while feeling the pressure that I have to face the coverage more strictly. I watched Blade Runner 2049 and Ford vs Ferrari using Apple TV 4K as the source device.

 

There are three network environments that have been verified:

 

(A) Connect the router to the Apple TV 4K directly with a regular LAN cable.

 

(B) Connect→ the S100 and Apple TV 4K with a regular LAN cable using an optical media converter between the router and the switching hub S100 (connection pattern (3)).

 

(C) Connect the router → switching hub S100 with a regular LAN cable and connect the optical media converter to the S100 and Apple TV 4K terminal to connect the optical LAN (connection pattern (4)).

 

Test3 (number)

What is the effect of using the Apple TV 4K with an optical connection adapter?

 

Using Apple TV 4K, which supports various video streaming services, we checked the effect of optical LAN connection on video content over the Internet. Apple TV's 4K & HDR video + Dolby Atmos audio content "Blade Runner 2049", "Ford vs Ferrari", etc.

 

DELA S100 Optical LAN

Connection Pattern (3)

 

DELA S100 Optical LAN

Connection Pattern (4)

 

Apple TV 4K is (A→ LAN-connected (router→S100→ Apple TV 4K) and (B) optically connected by OP-S100 between router and S100 (router→ optical adapter→ optical cable→S10 0→ Apple TV 4K/ Connection Figure 3), (C) Comparing the state via OP-S100 (router→S100→ optical cable → optical adapter → Apple TV 4K / connection diagram 4) just before Apple TV 4K

 

This is an important result, but this has resulted in a better-than-expected change in image quality. Listed in order of good image quality (C) → (B) → (A). The use of optical media converters improves image quality. And, the high effect was felt in the use just before the terminal.

 

Apple TV 4K's Blade Runner 2049 shows overwhelming footage from the beginning of Chapter 1. In (C), the focus surface at the up of the pupil which becomes a large picture at the beginning becomes thin and sharp, and the tone of the bokeh expression which is gradually out-of-focus from the mountain of focus looks seamless. Solar panels captured with a wide-angle lens (?) it is drawn sharp, and the texture that was a little sharp becomes more realistic. In the outdoor scene where the main character descends on Sapper Morton's house, the prospect of fog particles and floating feeling improves, and even the expression of the background changes, and the clarity of the dark part rises in the scene in the dim room.

 

"Ford vs Ferrari" is also a good impression. The tone of the scene where Ken Miles and his son live in magic hour in Chapter 21 is raised, and the view of the scenery and the saturation of the colorful guidance lights of the airfield also increase. I felt that improving the fineness of the focus surface was not a cheap thing that emphasized the outline, but an essential change in image quality that would allow information that had been spoiled by noise to come into view. In addition, the sound quality improvement is also impressive. The reality of the low range increases, and the exhaust note which is the charm of this work is pushed out and the power increases further. It is surprising that the sound movement feeling of the surround is emphasized more because the resolution of the sound of the small level is increased.

 

The image quality improvement effect by the optical connection ranged from the sense of detail, the good outlook, the expressive power of the dark part, the expressive power of the brightness, and the expressive power of the color. The low noise floor that can be heard in the audio environment literally improves the image quality in a "4-4" way. In addition, especially in video streaming services, the noise transmitted between devices using LAN wiring may have a significant impact.

 

In this interview, we realized the usefulness of optical LAN connection in audio applications again, and also found the usefulness in AV applications. Although there can be no defect of the data itself in a normal LAN even in an optical LAN connection in a network environment with a certain or higher quality, whether there would have been an impact on the recycled quality due to the influence of noise, this was better quality than expected. In the near future, I decided to introduce optical LAN connection in AV environment. If you see this, there's no way you can't do it.

 

The trick when using an optical LAN connection is the connection location and the power supply method.

 

Finally, I would like to mention two tips for optical LAN connection. One point is that the optical media converter should be used as immediately before the terminal as possible. The two points are to charge the optical media converter from a different power tap or the like from the reproduction device if possible, to separate the influence of noise from the power adapter from the reproduction device.

 

DELA's optical-connected option set and optical-connected switching hub are easy to deploy and effective. It's a must-see item for both audio and AV.

 

What you're watching

 

Streaming music:

"John Williams in Vienna" to "Imperial March" (TIDAL/MQA96kHz/24bit, FLAC44.1kHz/16bit), "Blinding Lights/The Weekend" (TIDAL/FLAC44.1kHz/16bit)

 

Streaming video:

Blade Runner 2049, Ford vs Ferrari (or Apple TV. 4K & HDR video + Dolby Atmos audio)

 

Reference equipment

 

When the audio is played

Speaker system: Monitor audio PL300II

Pre-main amplifier: Denon PMA-SX1 Limited

 

AV playback

Projector: JVC DLA-V9R

Screen: Kikchi Grace Mat 100 (120 inches / 16: 9)

AV Center: Denon AVC-X8500H

Speaker system: monitor audio PL300II, PLC350II, PL200II, PL100II, Eclipse TD508MK3, TD725SWMK2

 

 

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51 minutes ago, dbastin said:

there's a lot of expectation for auditioning on the Lumin X1 with the SFP port. Products such as this unit that supports optical LAN connections can be connected by installing an S100 with a regular LAN cable and an optical LAN (SFP) terminal, and adding a compatible module/cable. As with the earlier verification, I first heard it on a normal LAN connection and then switched to optical connection. (Connection pattern (2)) In the same way, in the impression that noise floor and SN ratio improvement on the sense of hearing is common, the goodness of the X1 with a certain skeleton of the mid-low range is further enhanced.

 

FYI.  Lumin X1 fiber network setup guidelines:

http://www.luminmusic.com/support-fibre.html

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