RCA/Power Cable run - Together

[tracyrick 10+ year member]

What kind of noises could I hear if my RCA and Power cable are next to each other? Should it be a hissing/static noise? Or could it be any kind of noise? I think when I did my install I didn't separate those 2 cables very well even though I read this tip 20 times.

I'm getting a noise sometimes that sounds like a needle running quickly over a record, scratchy but with tone. It's not a pop - it has more sound in it than that.

I regrounded my amps, and I think my HU is grounded twice. Separating my RCA and power wires will be a lot more work but I guess it's my next step...

Click to read more...

 

[spin dB 10+ year member]

In many cases if you run these together you will hear alt wine or a high pitched wining noise. I always run these on opposite sides of the car.

 

[helotaxi 5,000+ posts]

If you're using your chassis as your ground you'd better move your RCAs away from your chassis, too cause the same current running in your power wire is running in your chassis as well...doesn't make sense does it? If you understood the physics of induced noise, thinking that having your power wire and RCAs run next to each other will cause noise doesn't make sense either. Truth is that a twisted pair constructed cable, which pretty much all decent car RCAs are, are all but impervious to induced noise of the type you might encounter in a car. 99% of the time alt whine, which is evidence of a ground loop, is caused by a bad component ground. The other 1% is caused by a bad component. Is your HU a Pioneer by chance?

 

[Boulderguy 10+ year member]

+1 ^^ - thanks for debunking that one. Agreed on the ground loop almost always being the cause of engine noise & RCA's + power almost never.

If you've grounded your HU in two places that may a loop right there, but your noise doesn't sound like alternator whine, it sounds more electrical.

Silly question, but are all the RCA's fully connected, meaning not halfway in?

 

[tracyrick 10+ year member]

Thanks for the tips. I just spent an hour separating my RCA and power wires - about 6-12" separating them now (12" most of the way). My RCA does run on my chasis floor under my carpet, but for now I'm going to accept that. My RCA is Knuconceptz from their amp kit and I think shielded. Yeah, all RCAs fully connected, checked.

If I still get the weird sounds tomorrow, I'm going to pull out the HU (Alpine) and disconnect one of the grounds. I might also make my own chasis ground for the HU instead of just using the harness grounds.

 

[Boulderguy 10+ year member]

Even better, take a long section of 16g or so, connect to your amp ground, drape it over the seats & try that as your HU ground (disconnecting the other two) - this eliminates the loop created by the HU.

If that solves your problem you can take the time to run it proper.

If not, my guess is it's something in the components themselves - what you described is not a normal sound.

Hey, you're right up the street...//content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[helotaxi 5,000+ posts]

I might also make my own chasis ground for the HU instead of just using the harness grounds.

You should have done that from the begining. It's quite likely the source of your problem.

 

[iceteebone 5,000+ posts]

better yet just run the headunit ground to the battery. you could even for testing purposes, run a ground wire out your window and to the battery and see if that eliminates noise.

 

[LinxuS 10+ year member]

If none of those work, try upgrading your RCAs. I had a slight alt whine in my front comps, and I upgraded my RCA to KnuKonceptz Klarity line. Solved the problem for me //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Friend had the same problem with some crappy RCAs. I gave him my old JL Audio RCA, and it helped his by about 80%. There's still a slight wine though.

 

[tracyrick 10+ year member]

Okay, I'm going to do one of these. But which is better: Grounding to the amp ground location or the battery?

Does grounding the HU to the amp ground somehow prevent a "ground loop" but grounding to the battery would not prevent this?

Both options are about the same level of work to get to, so I'll just do the most effective one. I guess I don't understand ground loops yet...

My RCA's are KnuKonceptz Klarity that came with my amp kit, but thanks for the tip.

 

[squeak9798 5,000+ posts]

Okay, I'm going to do one of these. But which is better: Grounding to the amp ground location or the battery?
Does grounding the HU to the amp ground somehow prevent a "ground loop" but grounding to the battery would not prevent this?

Of those two; Grounding to the battery would generally be better as the actual cable itself would be shorter. The longer cable would have a higher resistance (holding gauge constant), which would be less desireable.

Really running it to the battery isn't absolutely necessary as long as you can find a suitable chassis grounding location. It's possible you might save yourself some work by finding a good chassis grounding point.

 

[helotaxi 5,000+ posts]

As the HU power is relatively low current a solid chassis ground is usually adequate. The factory harness can't always be trusted though.

 

[questionaire 10+ year member]

As the HU power is relatively low current a solid chassis ground is usually adequate. The factory harness can't always be trusted though.

I have never had this problem but could it be intercepting signals from whatever wires are under carpet???

 

[squeak9798 5,000+ posts]

I have never had this problem but could it be intercepting signals from whatever wires are under carpet???

//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

I would answer your question...but I'm not quite sure what you're asking.

 

[questionaire 10+ year member]

//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif
I would answer your question...but I'm not quite sure what you're asking.

When RCAs or power wire is ran under carpet could the stock wiring(under carpet)cause problems with each other?