4x XLR through Cat-Cable

[Whoops]

I know little about cat5 other than it is four twisted pairs. So how do you connect the XLR pins 1 from end to end?

All Pin 1's connect to the same cable shield.

This is common practice in Live Sound to send or receive 4 analog balanced Line level signals.

There's companies that do the sends to the PA system only using 1 CAT shielded cable.
1+2  PA L+R Array
3 Sub-woofers
4 Front Fills

 

[moamps]

.... In regular snake cable each pair has a vinyl jacket around it that creates a relatively large amount of space (2x jacket is 2-3mm maybe) between the pairs....

I worked with audio multicores made without that jacked, never experienced any  crosstalk issues. You can buy it still regularly.
And, IMO, stp data cables do not look much mechanically and electrically  different except missing drain wire on each pair.
https://shop.klotz-ais.com/50105-pl22y04-online.html
https://shop.sommercable.com/en/Cable/Bulk-Cable-Audio/Multipair-SC-Planet-FMC-100-0051.html
https://catalog.belden.com/index.cfm?event=pd&p=PF_9769

I use cat6 stp cables in small live gigs  without any problems (but not terminated with crappy RJ45 connectors).

 

[juliusbusch]

Sorry for the late response.

analog theory and design?

Yes please 

I checked out your web site but it seems the only way to pay is by bank transfer. Paypal would be so much simpler.

You are right. Until now there is now PayPal option during checkout, but I always offer this payment option to anyone who placed an order.

Been meaning to try this as well.  Is there a preferred pre-made CAT cable to use for analog audio signals?

I'm using CAT5 and CAT5e cables. They work perfectly fine for mic level and line level analog signals.

Thanks juliusbusch for sharing the docs,
but there's really cheap options for this, with these prices I don't see any motivation to DIY one:

I know... I think these metal ones are much better than mine and even cheaper.
However, I did this project for the fun and not for a commercial use, so... 

Nope. Just using logic.

Cat cable does not have shielding between pairs. So there will be electrostatic and electromagnetic crosstalk. Just spit-balling here but I think electrostatic will be dominant if the impedances are high and electromagnetic will be dominant if current is high. I don't think the typical line input impedance of 10K is particularly high wrt capacitive coupling so I think the primary concern would be electromagnetic coupling. In that case, a 600 ohm load would be about as low as one would expect for a line level signal. Lower levels would equate to lower current. So high level signal into 600 ohms running next to a 10K line is probably going to generate about the most electomagentic coupling that you would expect to see in reality.

Now is that crosstalk higher than your noise floor? If you have an otherwise very quiet source running into a converter, then I would be willing to bet a roll of toilet paper that you would see it on an analyzer.

UPDATE: Actually I must be wr-wr-wrong about this. All of the cables Whoops is posting about below use shielding that would only help with capacitive coupled crosstalk. In particular, SFTP is foil around each pair and then foil and braid around the bundle. But I don't think the extra foil would create enough space to reduce electromagnetic coupling. In regular snake cable each pair has a vinyl jacket around it that creates a relatively large amount of space (2x jacket is 2-3mm maybe) between the pairs. It would be interested to measuring the difference in crosstalk between a conventional CAT6 vs SFTP CAT6 vs proper snake cable.

I think crosstalk will increase with the transmitted power. To this day I never had any problems with crosstalk. That' all I can say... 8)