Stereo Hums when grounded to frame

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=55906
Printed Date: May 12, 2025 at 11:52 PM

Topic: Stereo Hums when grounded to frame

Posted By: mr2rock
Subject: Stereo Hums when grounded to frame
Date Posted: May 17, 2005 at 2:17 PM

Ok I isolated to where my noise is coming from. I have 0 hum if my stereo is only grounded threw the stereo's ground wire. But as soon as there is a ground on the frame it hums. At the moment it hums only when its screwed in. Do any of you know a trick to isolate this.

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Lazy people aren't lazy, they are just more efficient.

Replies:

Posted By: RedKatanaX9
Date Posted: May 17, 2005 at 4:49 PM

Why not just ground to factory ground wire then? You are introducting ground loop noise into your system if you have multiple grounding points. Is the frame grounding point free of paint/dirt/grease?

Posted By: mr2rock
Date Posted: May 17, 2005 at 6:12 PM

Ok I understand im introducing a grounding loop. Here is the issue now though. I get lower resistance to the negative terminal on the battery, because its an mr2 and the battery is closer to the reciever. This is why i get a grounding loop because the ground on the rca have a lower resistance than the ground at the amplifier, do to distance.

My next move im going to do, check the frame ground, relocate the amp grounds( better spot) then try it agian.

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Lazy people aren't lazy, they are just more efficient.

Posted By: geepherder
Date Posted: May 17, 2005 at 9:24 PM

Okay, you can run your stereo's ground wire to your amp's ground and see if the noise disappears.

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My ex once told me I have a perfect face for radio.