Cabling for AES50 (X32 - DL32)

[Dave Rowles]

Getting my head a bit spun on this. Hope someone can help!

I'm buying a stage box for my X32 rack so I can run 32 channels. Do I get:
Cat6e shielded with Neutrik EtherCon
or
Cat5e shielded with unbranded EtherCon

Or does it not matter?

[Dan LB]

As far as I know it does matter. A colleague of mine has reported issues with some cables for AES50 use, albeit on Midas PRO series desks - I can’t remember the exact details.

The official cable is Cat5e.

https://www.thomann.de/ie/klark_teknik_ ... gJWnvD_BwE

I can double check and post a photo for you in the morning when I get to work.

Dan

[Dave Rowles]

I think I’ve managed to find a cat5e with neutrik EtherCon, so I may just go with that anyway. Was just trying to get it all with the same supplier to save postage, but I think I’ll err on the side of caution and go with the one I’ve just found.

[RMCL]

The X32 was designed with an etherCon Cat5e connector to ruggedise the interface, although many people just used ordinary Cat6 (non-etherCon) cables.

However, with the large number of X32s out there, it has emerged that electrostatic discharge (ESD) can cause AES50 dropouts.

It has been found that ESD caused dropouts can be eliminated by using shielded Cat5E cables fitted with etherCon Cat5e connectors, the shells/bodies of which are electrically connected to the cable shields at both ends.

But as etherCon Cat6 connectors are not compatible with etherCon Cat5E connectors, this means that screened Cat5E cable fitted with etherCon Cat5e connectors have to be used.

[Dave Rowles]

Thank you! I’ll order the Cat5e with the ethercon then.

[Dan LB]

Thanks for the info RMCL.

Yes it was dropouts that my colleague was experiencing. The wrong cable had been supplied for that particular gig.

Here's a pic of the official cable supplied with a Midas PRO2

[AlecSp]

There's so much crap spouted about AES50 requirements!

The critical thing is that it's a minimum spec of Cat 5e (so not Cat 5) and shielded.
BehringerWiki piece on AES50 cabling requirements

Sadly, too many people don't understand the conventions used to describe CatX cable. But, in this case, we need STP (shielded twisted pair), FTP (foil twisted pair), SFTP (shieded foil twisted pair but definitely not UTP (unshielded twisted pair).

There's also the solid vs stranded question. Typically, solid cable should be used for an install, stranded cable for touring. Not that you can't use them the other way round, but solid cable will typically handle less well than stranded, and will be more fragile.

Specifying Cat5e as a requirement permits higher categories of cabling to be used. So you can use Cat 6 or Cat 7, but you'll be adding cost and getting less flexible cabling. For an install, no harm in using a higher category of cable, and these days it'd be unusual to see an installation lower than Cat 6 everywhere for consistency. But for touring use, Cat5e cable will typically be much more flexible than higher categories.

Ethercons - yes, always good practise to use them - but make sure you get the ones that mate with the connectors on the X32 and stageboxes (NE8MC & NE8MC-1 for Cat 5e, NE8MX6 & NE8MX6-T for Cat 6A), as there are multiple variants and some are designed to mate with Neutrik's "non standard" NE8FDY connectors. There's a whole world of Ethercon detail, which I've poorly simplified above.
BehringerWiki piece on Ethercons
Neutrik Ethercon catalogue

I'm not surprised the cable Dan mentioned experienced problems. While it's hard to find all the info on the cable, it's solid cored and *appears* to be unshielded.

For what it's worth, I've never had (nor should I expect) problems with VDC's Tourcat Flexible Cat 6A S/FTP stranded cable with Neutrik connectors.

[Dan LB]

Cheers for the additional info AlecSp.

To be clear, the cable in the photo I posted is the cable that was supplied with our PRO2. I have never experienced a problem with any of our 50m drums. I’ve searched for a bit more detail on this cable as a result of this thread and it doesn’t appear to be the same brand as the one Midas/KT supply. It has however, been in use for 6 years now with no trouble whatsoever - maybe they’ve changed their supplier, I don’t know.

The cable my colleague experienced trouble with was a different cable supplied by a hire company for a gig in a different venue. If I remember correctly, he told me that it was indeed UTP. They replaced it with the correct stuff and had no further issues.

To add to the list of decent cable I can recommend Belden CatSnake. Used for 12 years with zero problems.

[AlecSp]

To add to the list of decent cable I can recommend Belden CatSnake. Used for 12 years with zero problems.

Indeed, Belden's info page for CatSnakev describes CatSnake as Cat6a SFTP stranded cable with Neutrik EtherCons "downwards compatible with the existing CAT 5e EtherCon™ chassis connector." So it's ticks all the boxes.

Lots of people will get away with non-compliant cabling, as with using mic cables for DMX. Just because it works for you *so far* doesn't mean it's the right thing to use. Be informed, and then make a decision about what risk you are prepared to take. And, with AES50 cables in particular, be informed, check against spec and then make the decision as to whether you're spending your money wisely.

[Dave Rowles]

Hopefully the one I've ordered will do the trick. Living on the Isle of Man I've not many options if it doesn't work, and the gig I need it for is this coming sat.

Cheers for the advice!

[Sam Spoons]

I've just been shot down in flames for suggesting that Cat6e STP would work fine for AES50 because :-

Each pair has its own twist pitch, and AES50 uses all the pairs for different things than ethernet. It’s depending on the orange pair arriving at a certain time and the blue pair arriving at a certain time-because frankly, that’s cheaper to build than built-in error correction, as ethernet has.

If you go to 6e the twists are all different, so it’s orange pair is longer or shorter, same with blue - so parts of the data won’t arrive at the calibrated time.

I'm, a, pretty sure the timing differences would be orders of magnitude smaller than the clock rate of the connection, and b, I don't think digital works like that? But, I've been wrong before

[RMCL]

Hopefully the one I've ordered will do the trick. Living on the Isle of Man I've not many options if it doesn't work, and the gig I need it for is this coming sat.

Cheers for the advice!

Suggest that when you get the cable assembly that you check:
1. That the etherCon connectors fitted on the cable assembly mate with your Behringer X32 & S32 (which have etherCon Cat5E chassis mount connectors, which are not compatible with etherCon Cat6 connectors).
2. That there is electrical continuity between the shells of the etherCon connectors on the two ends of the cable assembly.

[Sam Spoons]

Yes, definitely good advice. CAT5 Ethercons can be used with CAT6 cable but a ready made cable would normally be supplied with the associated connectors. And there are well documented problems with when the screen is not continuous between the two devices.

[RMCL]

Yes - although shielded cable is used this does not necessarily mean that the shield is connected to the shell of the etherCon connector.

The Neutrix NE8MX cable connector carrier converts a pre-assembled RJ45 to an etherCon Cat5E/Cat6E connector. At https://www.neutrik.com/en/product/ne8mx there is a download that lists the RJ45 connectors from different suppliers that are compatible with the NE8MX, together with information on whether these RJ45 connectors are for shielded cable (or not), plus the CAT of cable that the RJ45 connectors are compatible with. It is possible for a shielded cable to be used with a RJ45 not designed to be used with a shield, resulting in the cable shield not being connected to the shell of the etherCon connector.

[Sam Spoons]

Yes, true, as you said, the spec for the X32 AES50 require that the screens be connected to the Ethercon shell at both ends.

[Dave Rowles]

Cable didn't arrive in time for the gig, so I had to use an off-the-shelf 2m CAT5e cable from PC World.

It worked, but obviously not a long distance, so I racked it all into the same rack and used good old analogue stage boxes.

Proper cable has just arrived so will check those things out!

Thank you all!

[jc051901]

I bought a cat6e shielded for the x32 going to the x16. I wanted to get the cat5e shielded, but nobody has it. And I needed it fast. Hope everything works out.

[BigRedX]

I wouldn't use any ethernet cable in a live situation unless it was extra rugged and sported proper Ethercon connectors by a reputable brand. Anything else is fine for one off emergency situations, but don't expect it to last in continuous usage especially in a rig that is repeatedly set up and knocked down.

IMO all consumer/office grade computer components are simply not robust enough for the demands gigging puts on them. Ethernet cables in particular are set and forget, and in those circumstances they work perfectly well. Just don't expect ordinary ones to still be working and making reliable connections after a month or two of weekly gigging.

Speaking from personal experience.

[MarkOne]

Not the same thing I know, but for our permanent install at our church, we’ve been running an A&H AR2412 to our SQ5 with shielded cat 6 off a drum I bought from screwfix with standard RJ45 plugs. And it has worked perfectly.

I wouldn’t do that for a portable solution, but for an installation, it seems fine.

[AlecSp]

Not the same thing I know, but for our permanent install at our church, we’ve been running an A&H AR2412 to our SQ5 with shielded cat 6 off a drum I bought from screwfix with standard RJ45 plugs. And it has worked perfectly.

The plain truth is that dSnake over AES50 is one of the massive benefits that A&H's SQ series has over X32. *Way* more resilient and forgiving of cables.

[BigRedX]

Not the same thing I know, but for our permanent install at our church, we’ve been running an A&H AR2412 to our SQ5 with shielded cat 6 off a drum I bought from screwfix with standard RJ45 plugs. And it has worked perfectly.

I wouldn’t do that for a portable solution, but for an installation, it seems fine.

Exactly. "Set and forget" just like network connections on desktop computers in the office. They work fine for years because they never get touched. On the other hand when I was in charge of such things the RJ45 connectors on cables attached to laptops used to need replacing every 6 months or so, because the locking tag would eventually break off and they would loose connection at a critical moment. I used to have to tell users with laptops to let me know the moment their RJ45 plug broke so I could replace the cable straight away and not when a large file transfer stalled mid way through.