Cat5 cables as microphone connections??

Thread Starter

MisterBill2

Joined Jan 23, 2018
19,341
I anticipate having to install a new sound system in a building that previously had a sound system, which has been stripped out. I anticipate about a dozen XLR microphone connections at one end of a large seating area, with the audio board at the other end. There is presently a steel conduit in place for the mic cables. What I would hope to do is run three "Cat5" cables thru the conduit , along with a single "ground" wire, thru the conduitto a junction block in a steel junction box at each end of the conduit. From that box on would be standard 2 conductor plus shield cables to each XLR jack. On the audio board end a similar arrangement. The single ground wire will connect with all the shields at each end, and serve as the other side of the phantom power circuit. Has anybody done something like this? Does anybody see any problems?
The motivation is cost. Mic cable is not cheap, while cat 5 cable costs a lot less as it is tending toward obsolete. And probably even cat4 cable is available and will still be OK at audio frequencies.
 

nsaspook

Joined Aug 27, 2009
13,526
I anticipate having to install a new sound system in a building that previously had a sound system, which has been stripped out. I anticipate about a dozen XLR microphone connections at one end of a large seating area, with the audio board at the other end. There is presently a steel conduit in place for the mic cables. What I would hope to do is run three "Cat5" cables thru the conduit , along with a single "ground" wire, thru the conduitto a junction block in a steel junction box at each end of the conduit. From that box on would be standard 2 conductor plus shield cables to each XLR jack. On the audio board end a similar arrangement. The single ground wire will connect with all the shields at each end, and serve as the other side of the phantom power circuit. Has anybody done something like this? Does anybody see any problems?
The motivation is cost. Mic cable is not cheap, while cat 5 cable costs a lot less as it is tending toward obsolete. And probably even cat4 cable is available and will still be OK at audio frequencies.
IMO you should do the right thing with the right cable if you want to try it. Shielded Twisted Pair (STP)
https://www.jeffgeerling.com/articles/audio-video/xlr-mic-level-balanced-audio-over-cat5e
I don't understand the split-pair connection as a single pair should be fine. Maybe trying to simulate Star quad cable: https://www.soundonsound.com/sound-advice/q-whats-special-about-star-quad-cable

Yes, there are also cat 5 line level audio converters that convert single-ended to balanced audio at the send and then convert to unbalanced at the receiver side.

Some devices for a DIY solution.
https://www.analog.com/en/products/ssm2142.html
https://www.analog.com/media/en/technical-documentation/data-sheets/SSM2143.pdf
 

LowQCab

Joined Nov 6, 2012
4,286
"Belden-Belfoil", Twisted-Pair or Multi-Conductor-Cable,
is what You will wind-up installing if You want a truly trouble-free installation.

Otherwise, just build a Box with 12-One-Watt-Audio-Amplifier-Chips to blast the Lines HARD,
then use any Wire that You can get cheap.
The Mixer-Inputs will need to be switched-over to "Line-Level", instead of "Microphone-Level".
You may have to "Pad-Down" the Level right before the Mixer to prevent overloading the Inputs.
This can work very well, as far as lack of Noise, Cross-Talk, and Level-Loss are concerned,
but it's awfully klugey and very cheesy, not at all proffesional, and not worth the trouble in any case.

If You use ANY Microphone(s) other than bog-standard "Low-Impedance-Dynamic-Microphones",
then you're on you own.
Your "Box" will then require special considerations for Input-Compatibility with special Mics.
.
.
.
 

Thread Starter

MisterBill2

Joined Jan 23, 2018
19,341
All of the microphones are either low-impedance balanced output dynamic mics or else mics using phantom power and providing the low-Z output. An array of remote amplifiers with remote power would be bad news from any point of view, both overly complex, excessively expensive, and much more distortion, and require a whole lot of room that is not available.
There are no single ended mic level signals in the system.
 

LowQCab

Joined Nov 6, 2012
4,286
Mr.Bill ??????
How did I not notice you are the Thread-Starter ?

Go ahead and try Cat-5,
if You can get an entire 500ft. Spool for free, or super-cheap,
just keep in mind that the Labor to install it probably can't be redone for free,
and, You may have no choice but to build that "Special-Box" anyway.

Who knows, since it's in EMT, maybe you'll luck-out and only get a small "Top-End-Roll-Off".
( Although there could be a myriad of other "weirdnesses" that could rear their ugly heads )
Networking-Cable has significantly higher DC-Resistance also.

Belfoil is specifically designed for the specific job at hand,
and hasn't been changed in ~60-years, because it just works perfectly every time.
Your mileage may vary.
Good Luck.

BTW, Belfoil is a great upgrade for CAN-Buss Networks in Noisy-Environments..
.
.
.
 

Thread Starter

MisterBill2

Joined Jan 23, 2018
19,341
If you are trying to avoid the cost of cabling installation, DANTE kit is likely out of your budget.

But how about this stuff?
Cat snake....

https://www.thomann.de/gb/the_sssna...MI4OygoIOOhgMVppKDBx3n-AFbEAQYASABEgKyFvD_BwE

Anything here to whet your wants?
The "Catsnake" looks like a ready made end termination of what I was considering. But a lot more expensive. What it does show me is that others are selling a package that does the same thing, and that is encouraging. Shielded network cable O might need to buy, what I have is not shielded. But the solid steel thinwall conduit should be adequate, if I run a single common wire along with them. And for 16 pairs that would be 8 x 24 L (four at each end)
 

dovo

Joined Dec 12, 2019
72
Audio over CAT5 is a thing...

Analog Audio over CAT5 https://soundtools.com/audio-over-cat5-systems-page.html

Analog Audio over Cat5: Everything You Have to Know
https://enhancedmedia.medium.com/analog-audio-over-cat5-everything-you-have-to-know-996cad54b659

AUDIO OVER CAT5/6/7 https://www.sescom.com/products/view/category/categoryslug/audio-over-cat567

XLR over CAT 5/6/7 https://www.epanorama.net/newepa/2021/04/17/xlr-over-cat-567/

Klark Teknik NCAT5E-50M Cat 5e Cable on Reel - 50 meter https://www.sweetwater.com/store/detail/NCAT5E50M--behringer-ncat5e-50m-50-meters-long


---------------------------------------------------------------------------------------------------------------------------------------------------------

CAT5 pair are twisted with different lays to reduce coupling but is this good enough? As nsaspook says, STP is best. Mogami 12-ch audio STP is $4.56/ft. 15-ch is $5.91. They are rated UL13 CL2X 60C

What CL2X is for https://www.datapro.net/techinfo/cable_ratings.html

Mogami W2933 12-Channel Audio Snake Cable

https://www.performanceaudio.com/pr...GJ2cN8vON1V428aUCz3oOaNXaTQIj4H0aAhPFEALw_wcB
 
Last edited:

Thread Starter

MisterBill2

Joined Jan 23, 2018
19,341
OK, it must work with even unshielded cable, although only one source admits that one pair is utiized to provide the "ground" connection required for phantom power. THAT supplier stated that for four channels with phantom power, shielded cat5 cable is required. the other supplier never mentions that.
So now I know what I need to know.
Many thanks to dovo for providing the links!!
 

Thread Starter

MisterBill2

Joined Jan 23, 2018
19,341
I just tried the "Sweetwater " link. And I know enough about them to know that they do not sell junk. And the time to pull four runs of cat5 thru 120 feet of conduit is really not bad at all. One pull with one helper to feed off the rolls. The fact is that amongst other things I also have pulled a whole lot of wire to earn my tuition way back when. So pulling the cable in is easy, relatively speaking.
 
Top