ECN Forum
Posted By: e57 Line In/Out Audio on cat-5? - 06/10/05 01:22 AM
Just fishing for opinions....
Line In/Out Audio via 60' cat-5 to RCA jacks?
Posted By: gfretwell Re: Line In/Out Audio on cat-5? - 06/10/05 02:01 AM
Electrically it works. The trick is isolating the 60hz hum.
Posted By: hbiss Re: Line In/Out Audio on cat-5? - 06/10/05 04:33 AM
I think you guys lie awake in bed at night just thinking up lame uses for CAT5.

-Hal
Posted By: e57 Re: Line In/Out Audio on cat-5? - 06/10/05 08:07 AM
It's just so 'available', and convieniantly run between my stereo, and computer sound card right now. Otherwise, I wait and do it right with 4 runs on RG-6 w/ F-RCA adaptors later, when I open the walls again. (when-ever that is?)
Posted By: giddonah Re: Line In/Out Audio on cat-5? - 06/10/05 01:37 PM
http://www.belden.com/college/college.htm

click on "Technical Papers" in the Cable Training section. Third to the last link in the Broadcast Audio/Video section is a paper on A/V over cat5.
Posted By: hbiss Re: Line In/Out Audio on cat-5? - 06/10/05 04:15 PM
Okay, okay. You may get away with it if you convert your unbalanced lines to low impedance balanced with transformers at either end of your UTP.

We do this to put audio for music-on-hold on runs of CAT3 where the source and telephone system is far apart. Sometimes the pair is even part of a multi- pair cable and we don't have problems with crosstalk or hum.

-Hal
Posted By: gfretwell Re: Line In/Out Audio on cat-5? - 06/10/05 05:39 PM
I have PC out audio going around my house from my MP3 players.
The problem I see most often is when one end of the audio line is grounded (PCs do that) and you are going to another piece of equipment with a grounded signal conductor (some stereo amps or any TV connected to cable). If there is a delta between those grounds it shows up as hum. Absolutely ugly was when I tried to go from the "out" of one PC to the "in" of another one in another building. You can get that same effect if you have a stereo amp with multiple inputs, one of them being grounded(that TV I spoke of).
"Fat wire" bonding will make most of this this go away (why stereos have the ground lug on the back) but that may not be practical over long distances.

BTW what type of transformers would you suggest?
Posted By: gfretwell Re: Line In/Out Audio on cat-5? - 06/10/05 05:54 PM
After reading the article I am convinced there is nothing wrong with using cat5 this way. You would need a spectrum analyser to see the problems they outline and I doubt anyone who has ever used a hammer drill or a shot pin gun could ever hear it. To all of those audiophools who say they can hear the oxygen in their cables I say "Huh?"
Posted By: hbiss Re: Line In/Out Audio on cat-5? - 06/10/05 06:02 PM
http://www.rdlnet.com/max_tx-series_products.htm#afc1f
http://www.rdlnet.com/max_tx-series_products.htm#afc1m
http://www.henryeng.com/matchbox.html

There are others, these are what I had on file.

-Hal
Posted By: e57 Re: Line In/Out Audio on cat-5? - 06/10/05 07:11 PM
That was an informative article...

No so concerned with ground loop noise, or should I say yet. It's an issue I can handle if need be.

Cross-talk would be an issue if I could hear the phone ring through my amp at a Gazzillion dB! Might even make an interesting 1/2 hands free phone. [Linked Image] Won't be sharing cable though.

The reason I was even thinking of it, was that all of the MP3 network devices are poor quality, and ad-ware based software. I got one and it is driving me nuts. Tries to sell me stuff everytime I start it up. Also doesn't operate from any other of my audio programs. I can listen at the office from the speakers there, but sometimes nice to listen from the living room, on the big amp and speakers. (Rotel, and B&W)

They do make a connector for this: http://www.levitonvoicedata.com/catalog/BuildPage.aspx?BuildPageID=8

I was wondering about distance, but noticed that these connectors double up two pairs. Which could help out on that.

I'll let you all know how it goes...
Posted By: hbiss Re: Line In/Out Audio on cat-5? - 06/10/05 07:22 PM
Forgot about those. What the heck give them a try, lots cheaper than the stuff I posted. What can you lose and you can tell us how they work.

Leviton also has the same thing for S video, I mentioned them in an old post. My question (or comment) then was they have to have a balun or transformer and it would have to be pretty small to fit into the jack insert. I wonder how well something that small will work with audio. Low frequencies need lots of iron.

-Hal
Posted By: gfretwell Re: Line In/Out Audio on cat-5? - 06/10/05 08:45 PM
If you are running PC based MP3 a DOS solution is what I find works best. (MPXPLAY)
There are also some old Windoze packages like the early Winamp that are not corrupted with unwanted bloat/spyware.
I like the DOS solution since it can be controlled from a keypad. That is what I run in the cars. It is also the basis for the pool bar jukebox I have running off a Seeburg 3W1 wallbox. http://tomszone.com/3W1.html
I have an old keyboard card that uses switches in the 3w1 to feed keystrokes to the PC. That is a dedicated machine with no problems.
The hum problems are all on the cludge I have in the house with 2 PCs, a ReplayTV, DVD/VCR combo, componant stereo setup, TV and 2 remote amps. I have things tolerable but not cured.

I think Hal's TX transformers will fix that
Thanks Hal
Posted By: techie Re: Line In/Out Audio on cat-5? - 06/10/05 09:59 PM
http://www.unicomlink.com/products/ibm_coax_av/A_V_devices.asp#4
Posted By: brianl703 Re: Line In/Out Audio on cat-5? - 06/11/05 02:32 PM
Cat5 has been used in the car audio world as the interconnect between amplifiers and car stereos with reportedly good results.


[This message has been edited by brianl703 (edited 06-11-2005).]
Posted By: Active 1 Re: Line In/Out Audio on cat-5? - 06/12/05 04:59 PM
I'll try using Cat 5e for the power wires on my next car streo. I'll uns 1 cat for the 12v and another for the ground. I'll let you know how it sounds. Maybe by the time I get around to that I'll be using cat 6.

Leviton loves the cat 5 also. I remember they want it used to power their camera system. I think they call for it on many of their products. Of coarse they are also tring to sell you their cat 5 plugs, jacks, etc. to go with it.

I have a few cat 5 questions:

What's the voltage / amprage rating for cat 5e?

Has anyone tried cat 5 for fixture wips yet?

I know intercom wire cost me $$. Has anyone used the cat 5 for that yet?

If I parallel the cat 5 how many do I need to replace a 3/0 wire on a srevice?

Do they may an underground rated cat 5 so I can use it for LV lanscaping lights?

How many inches do you need to bury cat 5?

Where do I get the red cat 5 for fire protection systems?

How do you keep the cat 5 from pulling out of the back stabs on the outlets?

If the CB is rated for only 1 conductor do they mean 1 entire cat 5?

Do they make a cat 5 with out so many whites? I want to use it for multi wire circuits so I don't need 4 neutrals.

Tom




[This message has been edited by Active 1 (edited 06-12-2005).]
Posted By: gideonr Re: Line In/Out Audio on cat-5? - 06/12/05 11:11 PM
CAT5e tends to be quite high resistance. I used it to feed some cctv cameras over 100 metres of cable and lost several volts at less than an amp. PoE uses 48 volts to try get round this problem.

BTW you need big iron in transformers for power.
Posted By: e57 Re: Line In/Out Audio on cat-5? - 06/13/05 07:41 AM
Active1, somebody might take those comments seriously...

Except for this one:
"I know intercom wire cost me $$. Has anyone used the cat 5 for that yet?"

For all but the door release circuit, it will work just fine. For that you need to double up the conductors. [Linked Image]

They do make direct burial cat-5, but would shy away from LV lighting, unless it were LED. [Linked Image]
Posted By: brianl703 Re: Line In/Out Audio on cat-5? - 06/13/05 02:39 PM
If you've ever seen how thin some of the wiring to the car stereo is on some cars (I think it's 22 gauge in some)...Cat5 wouldn't be much worse.
Posted By: John Crighton Re: Line In/Out Audio on cat-5? - 06/13/05 05:31 PM
I use cat-5 exclusively for my cars' starter motors. All that oxygen in the factory cables give the starter a harsh, reedy sound. With the cat-5, the starter has a much sweeter, more "open" sound. It's amazing, you can hear every tooth kissing the starter ring.

For best effect, be sure to support it on hand-crafted ceramic standoffs, kiln-fired over a pool of molten sodium. Letting the cat-5 get too close to the engine and frame just really kills the fast transients.

[Linked Image]
Posted By: brianl703 Re: Line In/Out Audio on cat-5? - 06/13/05 06:45 PM
Is that using "monster" cat5 or regular cat5?

If it's regular cat5, I can't believe you got those results from such an inferior grade of cable. Monster cable is better because it costs $2/foot. Monster cable makes everything it's plugged into work better.
Posted By: e57 Re: Line In/Out Audio on cat-5? - 06/14/05 12:11 AM
Guys, I got to tell you... Un-like some of the fooling around here on this thread, I saw the most ridiculous thing at the stereo store a few days ago. I'll have to go back and get a picture.

It was $9/ft "Monster" power supply cord, an example of which was made up in a display case, with a $1.50 Byrant cord cap on it. I had to bring up the "Cryogenic" gold dipped re-manufacture of a Hubble receptical seen on a few posts here with the guy at the counter. His reply was, "Oh those are great..." He then tried to sell me some "High end" speaker wire. Who needs that, I said, "I have several rolls of MC in the truck!" [Linked Image]
Posted By: e57 Re: Line In/Out Audio on cat-5? - 06/18/05 12:02 AM
I have some results....

Under ten feet, no noticable problems....
From that distance signal degrades at increasing ration to nearly nothing at 60', and hum rises at about the same rate.

So there we have it!

No I am going to try some baluns, and see how these work. http://www.hometech.com/video/muxlab.html
I'll let you all know...
Posted By: hbiss Re: Line In/Out Audio on cat-5? - 06/18/05 01:43 AM
I have some results....
Under ten feet, no noticable problems....
From that distance signal degrades at increasing ration to nearly nothing at 60', and hum rises at about the same rate.


How was the cable connected? Sounds like you soldered RCA's directly to a pair?

-Hal
Posted By: e57 Re: Line In/Out Audio on cat-5? - 06/18/05 02:12 AM
Na I gave these a shot... http://www.levitonvoicedata.com/catalog/BuildPage.aspx?BuildPageID=8
Posted By: hbiss Re: Line In/Out Audio on cat-5? - 06/18/05 01:41 PM
Well I'm a bit surprised but that confirms my suspicions. Can't see how they could do it in that small package.

Have you taken a look inside to see how they connect the RCA to the cable? I suspect that it's just straight through and I do remember you said they used two pairs?

Of course this doesn't bode well for their other jacks in that line such as the S video to cat5.

I think I would complain to Leviton about this. What are they good for?

-Hal
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