Cat6 for audio wiring convention?

[keeeth]

I'm not really sure if this is in the right forum but I couldn't see where else it would fit.

Is there a standard wiring convention or pinout for using cat6 as balanced audio interconnects?

I’m about to wire up a new studio with a lot of cat6 and if there’s an agreed convention I’d like to make sure I follow it

Whilst it obviously doesn’t matter how I do it as long as it all matches, I’m noticing a number of new products which use cat 6 for analog.
If they’re following the same convention I think it would be smart for me to make mine match it in case I add any of these units in the future.

 

[MagnetoSound]

I use CW1308, same as the BBC.

https://www.canford.co.uk/TechZone/Article/CableColourCodes

 

[Whoops]

Is there a standard wiring convention or pinout for using cat6 as balanced audio interconnects?

I also had this question when I was thinking in DIYing my own boxes of 4 XLRs to Ethercon connector.

I guess you question is what color pair goes to XLR1, what goes to XLR2 ... and so on...
And also what wire of each pair goes to pin 2 and what wire goes to Pin3,
Is that correct?

I quit the idea of building my own boxes, because these boxes are so cheap nowadays that it would be much more expensive for me to build it than to buy it already made, they're tremendously cheap

Some examples of the prices:

Whilst it obviously doesn’t matter how I do it as long as it all matches, I’m noticing a number of new products which use cat 6 for analog.

Sure, as long as you do the 2 analog/XLR ends with the same convention then it doesn't matter, the problem is if you use on one end a DIY box made by you in one convention and the other end you have a box from a manufacturer that used another convention.

If they’re following the same convention I think it would be smart for me to make mine match it in case I add any of these units in the future.

For sure, I agree. But to be honest I don't know if there is really any globally followed convention on that. Maybe each brand uses their own, can't be sure, I would go with the standard used by Dave Rat.


Soundtools from Dave Rat, use the T586A standard:



http://soundtools.com/pdfs/etherCONwiringdiagram.pdf

an here another standard seems to be called AES72/EB, not that the pinout standard is different for audio or DMX (lighting):






https://www.cat-core.de/en/Produkte/D-Serie-Retrofit

 

[Whoops]

Just for curiosity:

"Ethernet cabling has 4 pairs, the Green has 65.2 twists per meter, the Blue pair has 64.8 turns per meter, the Orange pair has 56.2 turns per meter, and the Brown pair has 51.7 turns per meter. This is done to spread and minimize the crosstalk influence of the individual pairs."

 

[ccaudle]

AES72-2019
"Application of RJ45-type connectors
and quad twisted pair cable for audio
interconnections"

Section 4.2 notes that "There are numerous commercial implementations which carry 4 audio links on QTP. These vary in their
assignment of links to the defined pairs."

"There is no consistency in link assignment across manufacturers. This inconsistency will result in links being
interchanged when equipment from different manufacturers is used at opposite ends of a QTP cable.
There is no consistent assignment of link polarity across manufacturers. When equipment from different
manufacturers is used at opposite ends of a QTP cable carrying analog audio signals this will result in
channel phasing issues and surround/stereo/mono downmix compatibility problems."

The standard recommends that implementations label which convention they use referencing the following table.
The type number describes the assignment of links to pairs and the type letter describes the link polarity on
each pair. The letter E shall denote implementations which assign the positive polarity pins to even numbers.
The letter O shall denote implementations which assign the positive polarity pins to odd numbers. The letter
M shall denote implementations which assign the positive polarity pins to odd numbers except for the pin
4&5 pair.

 

[sodderboy]

I wire all panel jacks to T568B, like they would all be used for networking. They are in addition to shielded pairs for MIC or LINE, coax for VID, zip cord for SPKR, etc. CAT6 lines are for headphone systems and utility like HDMI or RGB extensions, sometimes audio. I'm not sure why that SoundTools is using 568A, but look at every QUALITY straight RJ45 patch cable and you will see 568B. The balun interfaces I use for line level on CAT6 are wired to 568B, which is the standard.
That said, I hope that the OP does not plan to use CAT6 in place of serious, dedicated, main microphone lines. That would be a HUGE cheap-out with serenity and quality as the main victims. For microphone and line-level audio, save the future pain and keep with individual shielded twisted pair. CAT6 isn't magic, it's just 4 twisted pairs, maybe shielded overall. A mic cable is more than just a twisted pair. CAT6 tielines with balun boxes are great for special room-linking situations, but not for studio panel connections to consoles or racks of mic pre's.
I am not familiar with the sssnake or ST box, so I do not know if there are baluns in the boxes, or how they carry shielding, which is VERY key for P48 microphones. That ST box shorts 4 shields together, and I guess you have to run shielded CAT6 to have a shield? Not cool for for most microphones.
Mike

 

[Whoops]

That said, I hope that the OP does not plan to use CAT6 in place of serious, dedicated, main microphone lines. That would be a HUGE cheap-out with serenity and quality as the main victims.

Sorry but that's not correct.
Shielded CAT cable is used regularly on a lot of "serious, dedicated" professional applications for "main microphone lines" with no victims whatsoever.

That's pretty standard nowadays in Live Sound, the consoles are all digital so most PA companies don't even use multi-core cable for analog signals from stage to the FOH tech area.
They just install a lot of ethernet cables (smaller, lighter, easy to setup and remove) from stage to FOH , use them to digitally connect the Stage Box on stage to the FOH mixer, and have spare cables , some of those spare CAT cables are used for analog mic signals or line signals that may be needed from stage to FOH (both ways). Normally 4 analog channels is more than enough as there's not a lot of analog signals being used that way nowadays.

This has been standard practice for over 7 years now and I never, never incurred into any problem with that, no noise at all, just perfectly clean sound.

I also agree that if I was doing a studio with permanent cable installation, then I would use standard Multicore Mic Cable, but there's nothing wrong in using shielded CAT5E or CAT6, it has great specs for Audio

For microphone and line-level audio, save the future pain and keep with individual shielded twisted pair. CAT6 isn't magic, it's just 4 twisted pairs, maybe shielded overall. A mic cable is more than just a twisted pair.

For the above application only Shielded CAT6 or CAT5E cable is used,
I would never use any unshielded CAT cable for mic signals, neither I ever saw anyone doing it, also it's not possible to use at all at least with condenser mics as you need the shield for the phantom power 0V reference.
But using un-shielded CAT cable for Audio is not used at all.
It's Always Shielded CAT cable.

Also, CAT6 cable can have individual shields also, there's a lot of offerings for that from many manufacturers, this is the one I use and it's from S2CEB:

 

[Rob Flinn]

I finished wiring up a studio that someone else had started wiring with unshielded CAT6, including mic lines, line level signals. It was not my decision & I advised the owner against it. It was a job that had been started by someone else & I completed it, following the method the previous worker had used at the clients request. The condenser mic problem just had a single 24/0.2 wire daisy chained round all the tie lines pin 1's. When it came to testing it all seemed to work OK bar one or 2 damaged pairs from pulling the cables through some interesting holes. When we tested it on completion I didn't notice any interferance or buzzes & some of the mic runs were quite long. I have no idea if there have been problems since I finished. I think I would still use normal fst type multicores for my own place.

 

[Whoops]

I finished wiring up a studio that someone else had started wiring with unshielded CAT6,

I think I would still use normal fst type multicores for my own place.

I would also use normal/standard multicores for a fixed installation, but everything I said in my post is related to Shielded CAT cable and never to unshielded one.

The 4 audio analog channels over shielded ethernet CAT cable is a Live Sound thing and not common in studios, no need for that in a studio really. And the CAT5E or CAT6 cable used in Live Sound is all Shielded.
There's a lot of different products from different manufactures for 4 analog balanced signals over Ethernet cable and the reason for that it's because it sees a lot of usage and keeps growing.

My Live Sound 75 meters cable is composed of 4x Shielded CAT5E cables.
2 of them connect my 2 stage boxes from the stage to the console, the third one is spare or I use it to connect an Wi-fi router on stage to the console, and the forth one I use it for analog signals in case I need to send analog signals from FOH to STAGE or the other way around.

 

[sodderboy]

whoops, glad you agree!
Thanks for all the CAT6 use in live sound info.
Mike