Optical Network Configurations

[hltf]

9 hours ago, Assisi said:

I am aware that many posters in this thread use an EtheREGEN.  I tried an EtheREGEN in my network.  I consider in my situation the device was not as beneficial as other switches with optical connection capabilities.  My AOC connection is between a SOtM sNH-10G +sCLK_EX, and a Melco S100.  My network also includes 3 x Waversa and 2 x Nordost switches connected RJ45. 

John

 

Thank you for all this detailed information.  For now it is useful food for thought as I start thinking about what my next steps might be.

[Superdad]

On 4/27/2024 at 7:10 PM, Assisi said:

My AOC connection is between a SOtM sNH-10G +sCLK_EX, and a Melco S100.  My network also includes 3 x Waversa and 2 x Nordost switches connected RJ45. 

So that tallies up to around $12K+ in Ethernet switches!

 

Sorry if our humble—yet chock full of unique tech and costly chips—$680 EtherREGEN got lost in your mix. 

Obviously yours is not a typical use case…

[Superdad]

Phone glitch duplicate…

[Superdad]

Phone glitch duplicate.

[Superdad]

Phone glitch duplicate.

[R1200CL]

20 minutes ago, Superdad said:

$680 EtherREGEN

Any update regarding which year or month the new version will be available ?

[dbastin]

8 minutes ago, Superdad said:

So that tallies up to around $12K+ in Ethernet switches!

 

Sorry if our humble—yet chock full of unique tech and costly chips—$680 EtherREGEN got lost in your mix. 

Obviously yours is not a typical use case…

Assisi and I are on a forum down under where many experiences with ethernet have been shared.

 

I recall Assisi first had a humble Bonn 8, then got hooked with Paul Pang Quad and I recall it was around then he tried ER, Melco and Sotm.  He may have been grappling with not having enough (or sharing) power supplies and the ER didn't survive this competition and/not contributing the flavour he preferred so was moved on.  It was much later Assisi realised the benefit of disconnecting the cable sheild, so it is quite possible there was some 'defeating the moat' going on in the early period with ER - I certainly made those mistakes.  It seems to me the ER benefits a great deal from careful attention the cable shields and independent power source otherwise it might not perform its best.  

[audiobomber]

I have compared the ER head to head with a Silent Angel N16 and an LHY SW-10 in my system. Powered by a Pardo MiniTeddy supply, the ER beats both. I have read posts by people who compared an ER to a Melco S100 and preferred the ER, but I don't recall what ancillaries were used with the ER. As always, there's no "one true way" in audio, but the exceptional value of the ER is inarguable. 

[Assisi]

13 hours ago, Superdad said:

Obviously yours is not a typical use case…

As I said in my post above

“I am aware that many posters in this thread use an EtheREGEN”

It just wasn’t for me

I am aware that with the release of the EtheREGEN it was the start of the move to audio network switches.

My situation with more than one switch is not unique.  I am aware of others who have more switches than I have. One thing I have found in my situation is that 2 or more switches can be better than just one.  Each switch can add its own flavour to the outcome.  Through trialling it is important to determine the sequence of the switches, cables, resonance and interference strategies, network speed and power supplies.  With the switches that I now have, the network speed is limited to 100mgb.  I consider that is a benefit

I have never been pleased with optical until I tried the Cisco AOC. Initially I tried compatible AOCs.  Not impressed.  I have a box of various AOCs, SFPs and cables that I no longer use.  I always felt that whilst there was an upside to optical there was a downside.  There was a minor negative impact on dynamics.  With the Cisco AOC I am happy.

John

[Crom]

I was reading earlier comments about SFP28 being downwards-compatible with 1G/10G etc. I'm looking at various motherboard options for a new music server and this one looks interesting because it has 2 x 25G optic cages built in: https://servers.asus.com/products/servers/server-motherboards/K14PA-U12#Features

 

I'm interested in Cisco AOC cables or similar and wondered whether I can just use a standard 25G to 25G like this: SFP-25G-AOC5M Cisco 5M SFP28 to SFP28 Active Optical Cable (https://serversfit.co.uk/sfp-25g-aoc5m-cisco-5m-sfp28-to-sfp28-active-optical-cable.html?gad_source=1&gclid=EAIaIQobChMItMPj6YHqhQMVpZNQBh2Axwq7EAYYBCABEgJaUfD_BwE) or do I need to find a cable that takes care of the "downspeed" eg 25G to 1G?

Thanks for any help.

[jabbr]

39 minutes ago, Crom said:

I was reading earlier comments about SFP28 being downwards-compatible with 1G/10G etc. I'm looking at various motherboard options for a new music server and this one looks interesting because it has 2 x 25G optic cages built in: https://servers.asus.com/products/servers/server-motherboards/K14PA-U12#Features

 

I'm interested in Cisco AOC cables or similar and wondered whether I can just use a standard 25G to 25G like this: SFP-25G-AOC5M Cisco 5M SFP28 to SFP28 Active Optical Cable (https://serversfit.co.uk/sfp-25g-aoc5m-cisco-5m-sfp28-to-sfp28-active-optical-cable.html?gad_source=1&gclid=EAIaIQobChMItMPj6YHqhQMVpZNQBh2Axwq7EAYYBCABEgJaUfD_BwE) or do I need to find a cable that takes care of the "downspeed" eg 25G to 1G?

Thanks for any help.

It depends on where you want the network connection to go. If you are going 25->25 then an AOC should work (assuming its compatible with your SFP28 cage). I have no idea of a 1G SFP device will handle a 25G AOC cable. Its not that the cable cant do 1G its that the 1G SFP cage may not work with the 25G AOC cable

 

You are typically safer connecting a 25G SFP28 via e.g single mode to a 1G SFP

 

Now this also depends on the driver built into your motherboard which *should* autosense but might need to be manually set to 1G

[Crom]

25 minutes ago, jabbr said:

It depends on where you want the network connection to go. If you are going 25->25 then an AOC should work (assuming its compatible with your SFP28 cage). I have no idea of a 1G SFP device will handle a 25G AOC cable. Its not that the cable cant do 1G its that the 1G SFP cage may not work with the 25G AOC cable

 

You are typically safer connecting a 25G SFP28 via e.g single mode to a 1G SFP

 

Now this also depends on the driver built into your motherboard which *should* autosense but might need to be manually set to 1G

It would have been helpful if I'd provided what will be hanging off the other end. In the back of my mind was the fact that I would be plugging this into an etheregen!

[SQFIRST]

1 hour ago, jabbr said:

I have no idea of a 1G SFP device will handle a 25G AOC cable

 

Very unlikely that 1G cage will accept a 25G module. The form and dimensions of quad speed modules appear to be slightly bigger and different than sfp/+.

 

 

[SQFIRST]

Correction - QSFP modules will not work in 1G cage. Looks like SPF25 may physically fit into 1G. Interesting premise @Crom, do keep us updated with your journey.

[jabbr]

1 hour ago, Crom said:

It would have been helpful if I'd provided what will be hanging off the other end. In the back of my mind was the fact that I would be plugging this into an etheregen!

The question is, then, whether the EtherRegen will accept/work with a SFP28 AOC cable... it might or it might not. 

[audiom3]

What would be gained in going to 25G?  The only thing that I can think of is maybe, lower jitter?  But I cannot find anything conclusive regarding jitter spec.  Latency and/or bandwidth aren't an issue with 10G for home use.  

[jabbr]

52 minutes ago, SQFIRST said:

 

Very unlikely that 1G cage will accept a 25G module. The form and dimensions of quad speed modules appear to be slightly bigger and different than sfp/+.

 

 

Its not that the QSFP28 modules are quad speed, its that they are essentially 4x SFP28 co-packaged. To operate over a single mode LC-LC duplex cable the QSFP28 100Gbe module has to multiplex 4 channels, for example by using 4 different laser frequencies each carrying 25G

[jabbr]

15 minutes ago, audiom3 said:

What would be gained in going to 25G?  The only thing that I can think of is maybe, lower jitter?  But I cannot find anything conclusive regarding jitter spec.  Latency and/or bandwidth aren't an issue with 10G for home use.  

 

Of course the required jitter specs are published as part of the stressed eye and its conclusive that 25G requires a tighter spec than 10G. Unsure that matters for us though. The 25G spec is the first optical spec that includes multirate support ie 25,10,5,2.5,1 G in the same device --- multirate has been present in copper ethernet forever.

 

None of this is actually new, Ive been using 100Gbe i.e. QSFP28 at home for some years now, its just that the costs are getting down to reasonable for most people. I've also posted for a long time that I can't hear a difference in SQ going to 25 nor 100Gbe

 

This *is* a good time to make the point that the 100Gbe devices which require vanishingly low jitter in order to work, DO NOT use special power supplies nor clock crystals, rather the clocking electronics have become rather sophisticated

[SQFIRST]

I was thinking of the size of the QSFP modules which are bigger and spoke too early on the SFP28 which IS same size as SFP. Thanks for the follow up @jabbr.

Here is a chart that I found helpful:

 

[audiom3]

11 minutes ago, jabbr said:

 

Of course the required jitter specs are published as part of the stressed eye and its conclusive that 25G requires a tighter spec than 10G. Unsure that matters for us though. The 25G spec is the first optical spec that includes multirate support ie 25,10,5,2.5,1 G in the same device --- multirate has been present in copper ethernet forever.

 

None of this is actually new, Ive been using 100Gbe i.e. QSFP28 at home for some years now, its just that the costs are getting down to reasonable for most people. I've also posted for a long time that I can't hear a difference in SQ going to 25 nor 100Gbe

 

This *is* a good time to make the point that the 100Gbe devices which require vanishingly low jitter in order to work, DO NOT use special power supplies nor clock crystals, rather the clocking electronics have become rather sophisticated

Thanks @jabbr.  Very helpful info.  I will say, I thought I was near the pinnacle of SQ through fiber optics until I added an LHY SW-10 switch.  It (re?)clocks the optical ports too and not just the copper ports.  And what a huge difference it made to SQ to clock my fiber lead right before going into my Lumin U2 sfp cage.  Best tweak I've bought to date.

[SQFIRST]

17 minutes ago, jabbr said:

This *is* a good time to make the point that the 100Gbe devices which require vanishingly low jitter in order to work, DO NOT use special power supplies nor clock crystals, rather the clocking electronics have become rather sophisticated

This is good to know. What changes did you experience going to 100GBE devices with regards to power domain separation/control? I imagine your audio is still protected behind isolated power and clean power at the endpoint?

[jabbr]

21 hours ago, audiom3 said:

Thanks @jabbr.  Very helpful info.  I will say, I thought I was near the pinnacle of SQ through fiber optics until I added an LHY SW-10 switch.  It (re?)clocks the optical ports too and not just the copper ports.  And what a huge difference it made to SQ to clock my fiber lead right before going into my Lumin U2 sfp cage.  Best tweak I've bought to date.

 

You know completely honestly in this hobby when you hear something more pleasing to your ear you don't need to question it.

 

My posts are directed entirely at the theory of why something might sound better. I'm just using what we know about e.g. 100Gbe and how it works and what optoelectronics make it work. 10Gbe and newer require jitter measurements via stressed eye pattern testing and 1Gbe and older don't. My 100Gbe PCI-e card outputs vanishingly low jitter from my server despite bog standard PSU so really Mellanox nee NVidia in my case has performed a feat of engineering. Thats all really. 

 

Also to be clear, my audio area is protected by a heavyweight balanced power wall and cheap switching PSUs in my house, my fridge etc can't reasonably/appreciably penetrate that iron. If I had an ethernet switch within my audio power domain, then yeah all sorts of stuff becomes important.

[jabbr]

21 hours ago, SQFIRST said:

This is good to know. What changes did you experience going to 100GBE devices with regards to power domain separation/control? I imagine your audio is still protected behind isolated power and clean power at the endpoint?

Right, only optical and isolated power into my audio domain. No 100Gbe devices, only the audio endpoints -- I *have* used 10Gbe PCIe cards when I was building PC based endpoints. The endpoints are within the audio power domain and output USB etc so its reasonable to optimize them. That said @Jud recently posted the fiberoptic USB cable experience!

[audiom3]

6 hours ago, jabbr said:

 

You know completely honestly in this hobby when you hear something more pleasing to your ear you don't need to question it.

Also to be clear, my audio area is protected by a heavyweight balanced power wall and cheap switching PSUs in my house, my fridge etc can't reasonably/appreciably penetrate that iron. If I had an ethernet switch within my audio power domain, then yeah all sorts of stuff becomes important.

Yes, until someone like @jabbr posts about 100G tech and the lack of need for re-clocking 🤣 I am wondering how much better 100G is vs 10G and if upgrading a switch could do exactly what the OCXO in the LHY is doing.  Guess I will have to try a new switch at some point to see.

 

Nice job with the 'firewall'.  I did have two fresh 20A circuits installed around 4 years ago with (4) Oyaide wall outlets.  This made a tremendous change in noise.  Especially noticeable (or not noticeable now) with phono preamps.

[SQFIRST]

6 hours ago, jabbr said:

in this hobby when you hear something more pleasing to your ear you don't need to question it

Love this statement. Easy to get caught up in the pursuit and the details and overlook the simple enjoyment of it all.

 

2 minutes ago, audiom3 said:

I am wondering how much better 100G is vs 10G and if upgrading a switch could do exactly what the OCXO in the LHY is doing

There is a kind of enjoyment and satisfaction from putting something together and seeing it all work. Similar to the tactile feel of a vinyl rig. Technical comparisons may not cut it or even make sense sometimes but nothing wrong in enjoying it.