Alternator Whine Options

[GTS13]

Hey guys,
I just finished installing my new 6 channel amp but now have alternator noise. I've already redone my ground on the amp moving it to a different location even and that didn't fix it. I also bought a couple Ground Loop Isolators and those didn't fix it either so I returned them. Any other ideas on what to do? Only other thing I can think of would be to replace my alt with a bigger one?

The amp is a JBL GTO 755.6 II.

Thanks!

[AudioFreak]

One thing I've always used to find the source of a ground loop is to use shorting plugs.

This is what you need to make. You can make these without the resistor and just use a loop of speaker wire.



Start at the amp. Unplug your cables and plug in the shorting plugs. Start the car. If you have noise it's coming from the amp or it's wiring. If not move on to the cables themselves.

Plug the cables back into the amp and unplug them from the headunit. Using some female to female rca adapters connect to the cables and start the car. If you have noise try moving the cables. Or better yet just try another set of RCA's and see if fixes it. I've seen bad cables out of the box even expensive ones.

No noise... it's coming from the headunit. Try grounding the headunit somewhere else.

DO NOT PLUG THE SHORTING PLUGS INTO THE OUTPUTS FROM THE HEADUNIT!!! IT WILL BE BAD, VERY VERY BAD

One other thing to check is the condition of the grounds under the hood. I think there are 3 total. 2 off the battery and one off the engine. Pull them off one at a time clean the surface and ring and reconnect. It doesn't hurt to clean these every so often. When I bought my celi the lights would dim every time I hit the brakes until I cleaned the grounds in the engine bay. There was also a little bit of alt. whine until I did this.