Amp Noise

HI guys,

got an ongoing amp noise problem that i cant solve. Its a whine and rumble sort of sound that only appears when the engine is running. I have run the rca and power cables down seperate sides of the car, grounded the hu and grounded the amp using 4gauge cable. I made sure the amp is grounded to a well scraped part of the body, but none of these seem to work.

After reading some of your other posts, i have 1 or 2 questions:

- is it a good idea to run a common ground cable from the battery, and ground both the hu and the amp on this same cable? or,

- should i run a ground cable from the amp straight from the amp to the battery, and one straight from the hu to the battery?

Thanks,
chrisp83

p.s i have already upgraded the cable from the body to the battery to 4 gauge, & i have ran a brand new set of rca.

It sounds like you're grounded good, so this may be a case of faulty equipment.  Here's some things to check first, though.

Ensure the battery (also check electrolyte level) and alternator are both in good shape.  Have them both tested.  Check and ensure the battery terminals are good and tight, and free from corrosion.  Check the alternator belt for proper adjustment or excess wear.

You can try grounding the outside conductor on the RCA's.  How did you set your gain?  If it's too high, that can also produce engine noise.

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

thanks for your input geep. I think ive solved the problem already though. I ran a test cable in the following way:

Amp Ground-----HU Ground----->Battery negative.

All the line noise dissappeared even though i used only 10Guage cable for the test.
I'm yet to test it, but i think this is a good solution. Im gonna try it with the amp gain turned right up to see if this is a lasting solution.