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Cable lengths for power and rca's

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Old 06-20-2005, 04:53 PM
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Default Cable lengths for power and rca's

I intend on mounting my amp on the rear wall. Would a kit of 20' be sufficient for the power wire?

As for rca's, I'm consider running them straight down from the radio, near the center console then back. 16' enough, or go for 20'?

knukonceptz.com products any good? The power cables I'm not too worried about. The RCA's are more important. They sell a twisted/shielded set, (their krystal line), but it only comes in 4 or 6M lengths..

http://knukonceptz.com/productDetail.cfm?prodID=KRY4.6M $38 or so shipped for a set of 4.

Last edited by GPz1100; 06-21-2005 at 12:12 AM.
Old 06-20-2005, 10:23 PM
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I'd do 20' and 20'. I just ran 18' power and 17' RCA's in my car. The amps are on the "floor" of the hatch though, not the rear wall. The power wire we cut off about a foot I think. The RCA's are run along the kick panels down the sides of the seats, not the center console, so it might have taken up more length that way but the RCA's came out to be a perfect length. If you're going the extra few feet to the rear wall I'd suggest 20'. 16' might be enough if you run them through the console but it might be close.
Old 06-21-2005, 12:06 AM
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Its better to have too much than too little , I mounted my amp on the front side of the trunk and ran 20' RCA along the side and had about 5 feet of slack and 20' power also along the side and had a few feet extra. I would recommend running the RCA up the passengers side and going through the glovebox its much easier than trying to find your way in the drivers side, By the way, does anyone know of a good place to get through the firewall for power? I just kinda went inside the door and fender ...
Old 06-21-2005, 12:15 AM
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Luna,

It's been recommended to go straight down out of the radio rather than across then down.

The installer who recommended this mentioned there were other wires in the dash, and by going across, there is more potential for noise to enter the signal.

I was going to pull the center console out, and run the cables on the side of the hump just to the side of the center console.

As for the power wire, there's the big grommet behind the pcm.. Exits somewhere behind the glove box..
Old 06-21-2005, 11:29 AM
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if you're any good at soldering, make your own RCA patch cables out of Cat-5 ethernet cable. that's what i did, and it works just as good as (or better than) pre-made patch cables. also, they're much cheaper to make, and it's not as thick, so you won't have as much of a bulge under the carpet from the cable.

all you need is some solder-on RCA tips that you can get from Radio Snack for like $2 - $3 per package of 3 pr., the ethernet cable, and the iron/solder/flux.

if you look at any pre-made twisted-pair patch cables with a clear insulator sleeve, you will see that it's the exact same stuff as Cat-5 cable, only not as many twisted pairs in the sleeve.
Old 06-21-2005, 11:33 AM
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02Z28LS1

Good point.. Cat5/6 however has no braided shielding, its just twisted pair.

My HU does have 4V outputs so I wonder if I really need the braid though.

I got a good 900' of cat6 in a box here used from a previous network install. Not very flexible stuff.
Old 06-21-2005, 03:37 PM
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The signals used in ethernet are much more sensitive than those in your audio system. If you can run a network without problems on cat5/6 then I wouldn't be worried about interference. plus you could always go buy some shielded twisted pair (stp) Cat5/6 if you are really worried about. Or you could do what everyone else does and buy a flipping rca cable from radio shack!!
Old 06-21-2005, 05:01 PM
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Originally Posted by Luna
The signals used in ethernet are much more sensitive than those in your audio system. If you can run a network without problems on cat5/6 then I wouldn't be worried about interference. plus you could always go buy some shielded twisted pair (stp) Cat5/6 if you are really worried about. Or you could do what everyone else does and buy a flipping rca cable from radio shack!!
You're not entirely correct.

Ethernet is a digital system, with distinct on/off pulses for different voltage intervals. There is also some sort of ecc in this transport medium.

With the car rca's, the signal is strictly analog. Anything that doesn't belong in the signal is likely to get amplified and will be heard at the speakers.

The better question is, is TP sufficient to deal with noise present in an automotive audio system...

I think a few extra $$ spent on shielded cable might help with some headaches down the line.
Old 06-21-2005, 10:06 PM
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Originally Posted by GPz1100
You're not entirely correct.

Ethernet is a digital system, with distinct on/off pulses for different voltage intervals. There is also some sort of ecc in this transport medium.

With the car rca's, the signal is strictly analog. Anything that doesn't belong in the signal is likely to get amplified and will be heard at the speakers.

The better question is, is TP sufficient to deal with noise present in an automotive audio system...

I think a few extra $$ spent on shielded cable might help with some headaches down the line.
Thank you.

And this will help prove how hard it is for Noise to enter a system, and how Not good the CAT 5/6 vs RCA is.

It took a large Transformer to Induce noise.

http://www.installer.com/tech/cat5.html

Great site to Browse. Guy knows his ****. And provides real world testing. Not just Theory.
Old 06-22-2005, 11:21 AM
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Richie,

Good comments from an alternative perspective.

My point was simply that we're talking about two different encoding systems.. One being analog, other being digital. It would not be appropriate to compare these systems in terms of noise suppression because they are so fundamentally different. Your link reinforces this idea.



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