Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Dave Cividanes]

Hello

I was wondering if anyone has experience with passing line or mic level audio over cat5e?

I was thinking of using shielded Cat5e or 6 for this purpose instead of using mic cable.

Also was wondering if wiring up a XLR with it is there any color code you should go with for a natural noise cancellation like the way a cat5 connector is wired up.

Thanks in advance for any and all info on this.

[Hal Bissinger/COMSYSTEC]

Let me answer your question with a question. What you are doing is substituting STP CAT5e or CAT6 for audio cable. Aside from being more expensive, solid wire, 3 wasted pairs and more difficult to terminate on a XLR, what's your reasoning?

-Hal

[Dave Cividanes]

Well the cat5e is only like 125 bucks for  a 1000ft.  So if i have a lot of single runs it may cut down on cost. I don't think it will that much harder to put a end on it. Anyway i just thinking about it and was wondering if anyone had ideas about it thats all.

[Mac Kerr]

Dave Cividanes wrote on Thu, 12 March 2009 23:40

Well the cat5e is only like 125 bucks for  a 1000ft.  So if i have a lot of single runs it may cut down on cost. I don't think it will that much harder to put a end on it. Anyway i just thinking about it and was wondering if anyone had ideas about it thats all.

And Belden 8451 is $150/1000'. Not much of a savings to go with solid wire. Neither wire is suitable for portable use, they are install only.

With CAT5 you need to use one of the 4 pairs as your audio pair, or you lose the noise immunity. I use CAT5 for audio runs in an installed cable plant that has a lot of spare CAT5, and little or no audio wiring. At line level it is fine, I would hesitate to use it at mic level.

Mac

[Jason Lavoie]

Mac,
do you have any experience running line level over cat-5 in close proximity to (or in the same conduit as) 70V speaker lines?
don't ask me why, but I may have to do just that soon.
in theory it should be ok, but I would feel better if I knew someone who had pulled it off before.

Jason

[Hal Bissinger/COMSYSTEC]

do you have any experience running line level over cat-5 in close proximity to (or in the same conduit as) 70V speaker lines?

Well I do and I can tell you it ain't going to work. Any job we have ever done that had 70v wiring and UTP telephone CAT3 or data CAT5 within a few feet had crosstalk. There was no effect on the connected equipment but with audio there will be a problem.

Now I assume you are talking about STP and I would like to know where you are going to get that for $125/M especially if you need a plenum listed cable. And that is for CAT5e. Shielded CAT6 plenum has to be astronomical.

I can tell you that I always get a bad taste in my mouth when I see CAT5 used (or misused) as a "universal" cable. CAT5 and CAT6 are for data or similar yet I've seen it used for anything from doorbells, thermostats, to intercoms and telephone. There is nothing worse than seeing everything wired with CAT5 because you can't tell the data from anything else. That kind of work just cries amateur. Use the right cable for the job.

-Hal

[Karl P(eterson)]

I have over 250K of Cat5 in a building of mine right now and it carries everything from building control systems, to thermostats, to security systems, to phones, to digital signage networks, to ethernet and POE, to anything else you can think of.

The funny part is it is all like that because that is what all the different manufacturers and products want these days.

It isn't amateur, or rather right to assume there are amateurs involved, to see a lot of Cat5 used for everything these days, that is just a sign of the times. While it is true that the different wiring plants should have different colors, it may also be the case that the cable was simply bought lump sum and there is only one color to work with. When dealing with 50 to 100 K or more there is massive discounts to be had by buying single color.

What _IS_ amateur is the lack of wire labeling and separate cable paths for separate plants.

That said in my application we are using about halve a dozen colors to denote different systems, but that is only because we needed enough of all the different colors to meet the price breaks. Otherwise I would have just got single color and paid even more attention to keeping our cable paths separate.

Now, to the OP, I would never run audio over Cat5 unless I _had_ to. You are also incorrect about it being cheaper. I can buy West Penn mic cable all day long for cheaper than any reputable Cat5 cable. Also Cat5 is a large cable to be pulling in large multiples.


Additionally, if you need to transmit audio over Cat5 I would use some good balun systems such as RDL, or any of the other high quality manufacturers. Now, I will admit to using Cat5 to run audio "Dry" in a few circumstances, but those were under 20' and at line level. I would hesitate to make a practice out of it. I would absolutely refuse if I knew I was in close proximity to a 70v line.

Karl P

[Hal Bissinger/COMSYSTEC]

The funny part is it is all like that because that is what all the different manufacturers and products want these days.

I understand that. If a system is designed for it that's fine and I realize there is a lot of stuff out there that is. But trying to make it work or using it in an application where it's not intended just because that's what somebody has or it's cheap is what gets to me. You see that all the time usually from sparkies because that's all they carry on the truck. Ever try to figure out what sparkie had in mind when he wired a heating-cooling thermostat with it? One guy on another board was even wanting to make jumper cables out of it.

-Hal

[Dave Cividanes]

thanks guys for all the info. it seems as i have looked into this a little and seems like some people think thats its ok to do so. one thing they are saying if you do mic level then you should bump it up to line level before sending.  Seems like there are mixed feelings about this topic.

let me know what you think about the read.

http://www.blue-room.org.uk/lofiversion/index.php/t11615.htm l

[Brad Weber]

I think Hal nailed it earlier, why are you thinking of using CAT5?  What I get from the referenced thread as well as from other sources is that you can run audio on CAT5 and it may make economic sense if the CAT5 is already in place or if you use it for multiple signals, however it would rarely make sense to use CAT5 for individual audio runs.