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I think I have alternator noise

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Old 06-25-2008, 08:46 PM
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Default I think I have alternator noise

so everytime i accelerate or decelerate, i hear a high pitched whine through the speakers that rises and falls in volume according to engine rpm. what is it and how do i get rid of it? it's driving me crazy!
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Old 06-25-2008, 09:19 PM
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Sounds like a warranty issue.
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Old 06-25-2008, 09:38 PM
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nope. i'm running 2 amps, subs, components, and an avic d3. it started after i installed all my car audio equipment.
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Old 06-25-2008, 09:44 PM
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Check your grounds! Also are the power wires and RCA's wires away from each other? It sounds like a ground loop.


Good luck!



John
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Old 06-25-2008, 09:56 PM
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rca's and power wire are away from each other. i think the grounds should be good but i did leave them a little long. i plan on fixing whatever it this weekend when i install my new subs since i'm going to have the trunk torn apart anyways. if it is ground loop, how would i go about fixing that?
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Old 06-25-2008, 09:56 PM
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It sounds like induced noise from a ground loop. Check your ground connection for the amps. It needs to be as close to frame as possible and needs to be entirely free of debris and paint. Since these cars are designed as a unibody vehicle rather than the older body-on-frame design, it is a bit easier to induce noise by way of a ground loop. This occurs when there is a difference of potential between ground points within the audio system. Since the majority of the electronics in the vehicle are grounded to the subframe up front, and there really isn't a solid frame rail that extends all the way to the rear of the car, there will be a difference in potential between ground points on the subframe up front and ground points in the rear of the vehicle. Often, with unibody cars, the only way to get rid of this induced noise is to ground all of the audio equipment, including the radio, at the same location.
You can try using ground loop isolators on the RCAs, but this typically produces poor sound quality and makes the highs sound very watery, like they are in a well.
Good luck. I hope this helps.
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Old 06-25-2008, 10:02 PM
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well, if it's a crappy ground, then i'll have to re do it and shorten the cable. where would you recommend grounding everything to make sure it's done properly? also, you're saying the radio ground sucks, but where do i ground the radio?

it's a real shame. i have some of the nicest equipment i've ever owned and this one thing is killing me!
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Old 06-25-2008, 10:10 PM
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How long are your ground wires from the amp? Also check the ground to the radio.



John
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Old 06-25-2008, 10:45 PM
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my grounds from the amp are less than 2 feet, but more than 18 inches. the radio ground is the factory one.
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Old 06-25-2008, 10:56 PM
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Originally Posted by randomsuper
my grounds from the amp are less than 2 feet, but more than 18 inches. the radio ground is the factory one.
I would shorten the grounds to about a foot or less. I believe that might be the problem. Also double check that the area (ground) is free from paint and its attached to metal (bare) at all ground locations.


John
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