Should I ground my RCA shields?

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=12233
Printed Date: June 01, 2024 at 12:00 AM

Topic: Should I ground my RCA shields?

Posted By: grubby
Subject: Should I ground my RCA shields?
Date Posted: April 15, 2003 at 6:06 AM

I installed my amps & crossover in back of my truck’s seat. I have a whine that is related to the engine rpm(s). I thought it was coming from the alternator and installed a 150 amp alternator filter and I still have the whine. I made my own RCA (large stranded center w/ copper shield) cables and suspect the whine is from the ignition. Should I ground the RCA shield? Is there something that can be done as the stereo sounds great with the engine off .

thanks

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larryo

Replies:

Posted By: bberman1
Date Posted: April 15, 2003 at 8:58 AM

How did you run your power and rca cables thru your car?

Posted By: wolfman_74464
Date Posted: April 15, 2003 at 11:08 AM

if any of your audio lines low level or high level are chasis grounded you will damage your outputs

Posted By: wvsquirrel
Date Posted: April 15, 2003 at 10:06 PM

Check your grounds. Make sure they are bare metal and connected to the frame, not a parcel shelf. Make sure your RCA's/speaker wires and Power wires are run down opposite sides of the car, or at least as far apart as you can get them.

You might try some other noise filters as well if you have already done what I mentioned above. Here are some links to get you started...

David Navone Noise Filters
15 or 25 amp inline noise filter

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Squirrel
"No more Cpt. Kirk chit chat"
If its too loud, then you're too old
Donate to the12volt.com

Posted By: wrencher_25
Date Posted: April 16, 2003 at 2:50 AM

First of all, are your speakers running of the amp? Or is your amp just running a sub? Like Squirrel said, power line and RCA's should be running on opposite sides. There was a video in school that had David Navone and Richard Clarke talking about alternator noise. They all sourced from the grounding points. The farther away you put the grounding point the less noise was visible. So try making your own ground and running it as far away from the alternator as you can. Hope it works.

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Andrew Weitzel

MECP First Class Installer

Posted By: grubby
Date Posted: April 16, 2003 at 4:06 AM

Thanks everyone that replied .....

I ran a 18” 1/0 ground to the truck's frame with using a grounding block within 12" of the amps (that are located in back of my truck's seat). Then I ran a 9" long / 1 1/2 wide cooper braided bonding starp from the seat's mounting bracket to the same amp grounding block to bond the truck's body to the frame.

In my attempt to use More's Law ("If enough is enough, More is better, too much is just right") I think I created my own problem.
I think the problem is with the four coaxial cables (center stranded with a cooper shield) that I made to connect the head unit to the crossover that is under the driver's seat. These four cables are large and fail to have the twist that helps to prevent the RF generated by the truck's ignition system that is just on the other side of the firewall (within 6 - 8 inches) I just bought the manufactured twisted pair connector cables with a foil shield and will install them today.

grubby

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larryo