AES 72 Spec and usage

[pucho812]

Has anyone here been doing anything with Audio over shielded RJ45 (cat5e, etc)

I have been thinking about playing with this for sometime in new studio builds cat5E cable is quite inexpensive.
I know guys like Dave Rat have been a good proponent for such connections.

I thought about using it for line level I/O but wondering about mic signals as well.
My thought is to make DB25 - duel RJ45 for patch bay runs to and from the gear.

 

[kags]

@thor.zmt mentions cat6 stp a bit. I’ve been eyeing it, too.

Post in thread '"Boutique" opamps from chinese vendors. Anyone tested?'
https://groupdiy.com/threads/boutique-opamps-from-chinese-vendors-anyone-tested.84892/post-1105425

 

[cyrano]

I've used all sorts of UTP for mic audio signal. Works pretty great. And unless you're in a very hostile environment it doesn't even need to be shielded. When you use UTP that's already in the building, you need to check for network activity on parallel cables. That can be a pita on long runs. Depending on the UTP, beware of cable runs of over 50 m. That's where problems appear and since the noise is faint, you might miss it when preparing.

These days, I use a couple of appsys.ch boxes to send 32 channels over one UTP, up to 75 m. But that's digital, of course.

For audio, you can forget the categories. I've never seen any UTP that doesn't work. Cat 5 and cat 6 only matter for network use. Cat 6 has different twisting speed on each pair, fi. But there's no effect on audio.

I started using it because I have boatloads of it. Mostly unshielded and older. If you find them somewhere, old IBM shielded cat 5 is great. Tough, best RJ45 connectors out there.

 

[thor.zmt]

For audio, you can forget the categories. I've never seen any UTP that doesn't work. Cat 5 and cat 6 only matter for network use. Cat 6 has different twisting speed on each pair, fi. But there's no effect on audio.

Yes and no. I recommend STP for starters, not UTP. And Cat6 and up have separate shields per pair, It becomes relevant in multicores.

And if you buy a box of CAT STP, you "cable for life".

Thor

 

[pucho812]

Yes and no. I recommend STP for starters, not UTP. And Cat6 and up have separate shields per pair, It becomes relevant in multicores.

And if you buy a box of CAT STP, you "cable for life".

Thor

Interesting. Thanks for that.

 

[cyrano]

Yes and no. I recommend STP for starters, not UTP. And Cat6 and up have separate shields per pair, It becomes relevant in multicores.

And if you buy a box of CAT STP, you "cable for life".

Thor

Yeah, forgot about those shields. I've never had trouble with UTP, though. But I mainly used it as a 4 channel patch cable. These days, I patch with optical (ADAT).

 

[pucho812]

So I did some kicad and made up 2 boards, one is DB25 to dual rj45 the other is neutrik RJ45 to solder pads so I can wire in XLRM, XLRF"


After today's wiring at my buddies studio taking a day to work out 1 b-gauge patchbay, I really want to experiment and have a full studio wired with STP.

 

[DB_]

My home hobby setup fits in a single rack and I would love to replace all of my cabling with Cat6. I’ve got a lot of 3m DB25-TRS looms coiled up in the bottom because it’s more expensive to get shorter lengths!

So I did some kicad and made up 2 boards, one is DB25 to dual rj45 the other is neutrik RJ45 to solder pads so I can wire in XLRM, XLRF"

Here’s some prior art:
https://quadtwistedpair.com/
https://like.audio/category/aes/db25-aes-59/
https://groupdiy.com/threads/aes72-data.80105/

LinkAudioDesign has a couple of RJ45 to XLR/Combo PCBs for €5.99
https://www.linkaudiodesign.de/product-page/cat-to-xlr
https://www.linkaudiodesign.de/product-page/cat-to-combo-xlr

and a model to 3D print a case for them:
https://www.printables.com/@linkaudiodes_1233690/models

The layout is a bit more suitable for a stagebox than in the back of a rack but it’s a cheap nifty off the shelf module that could be useful.

 

[ruffrecords]

Damn, I wished I had thought of this before. Recently I was busy crimping pairs of 8 way Molex connectors to do this job. If only I had thought of RJ45 it would have saved me a lot of work.

Cheers

Ian

 

[iomegaman]

So I did some kicad and made up 2 boards, one is DB25 to dual rj45 the other is neutrik RJ45 to solder pads so I can wire in XLRM, XLRF"


After today's wiring at my buddies studio taking a day to work out 1 b-gauge patchbay, I really want to experiment and have a full studio wired with STP.

I've thought about this but these products are actually quite cheap...and already ready to go...

https://www.catherinenorthelectronics.com/products/qtp


I've been in the process of changing over my patchbay to a Bantam TT bay (those whirlwinds are built like tanks and pretty great)...I picked one up for $30 at my local surplus electronics...but I'm tired of long snakes/etc and for one of the other equipment racks I got to thinking about doing what you are suggesting...found these guys with premade DB25>>>Quad Twisted pair....so my plan is to reduce the head of the DB25 snake to a quad twisted pair and bring it into the bantam patch bay...

 

[pucho812]

I've thought about this but these products are actually quite cheap...and already ready to go...

https://www.catherinenorthelectronics.com/products/qtp

nice. But with my current situation for 20 bucks, I can make several for the price of one.

 

[jeremynothman]

Has anyone here been doing anything with Audio over shielded RJ45 (cat5e, etc)

I have been thinking about playing with this for sometime in new studio builds cat5E cable is quite inexpensive.
I know guys like Dave Rat have been a good proponent for such connections.

I thought about using it for line level I/O but wondering about mic signals as well.
My thought is to make DB25 - duel RJ45 for patch bay runs to and from the gear.

We use it all the time in live sound for sending a few signals from A to B. I work at a venue where we have CAT7 lines throughout the venue and all our in-house stuff happens over Dante, Sometimes it's used for sending a few analogue lines, but often visiting acts have their own FOH consoles, and where we can avoid it we avoid another DAC-ADC layer by sending AES3 through an XLR-CAT5 converter to send signal directly to our system processor.

I've seen people use it for mic signals, but I feel it could be questionable in many environments. I wouldn't want to send that over to my FOH desk 50 cable-metres away.

 

[pucho812]

50M is 164 feet roughly.
That way more then I envision I ever would need.

 

[jeremynothman]

Of course, for a regular patchbay you don’t need that! But we’ve got a 10m deep stage that’s about 30m from the FOH position, and the Ethernet Patchbay and routers are in backstage. At least 50m cable run, probably more like 70m.
In short, it works!