Let me start by telling the setup I have in my truck:
I use my empeg as the main receiver and since I dont have a tuner, I have kept my cd-player in the truck as an aux-in which has been installed where the cigarette tray use to be. Well, because the empeg is now the main unit, I had to add an amp to support my factory speakers (Woo Hoo). I now have my empeg, a 250W amp pushing 4 factories, and a 250W amp pushing 2 8" Rockford Fosgates all compacted into a single cab 1994 Ford Ranger. (Custom built box for the 8's behind the seat)
After the empeg install, I had a problem with a ground loop noise until this past weekend. The noise I was hearing was the so called alternator wine along with the static. I went through and checked out just about all the possiblities to solving the problem including:
1) Double checking my ground connections
2)Grounding my sled
3)Replacing my RCA cables
4)And inserting a grounds loop isolator
Only the grounds loop isolator had any affect and it only cut the noise in half. So I kept trying to figure out what was it that was causing my ground loop to have a hole somewhere. I even went through
this flow chart from crutchfield and still couldnt find the problem. Well, I was kinda still trying to figure something out so I was checking things once again and to my dismay I found that my RCA jack on the amp itself had a short in it. I could hold the jack up and it would work fine but if I let it go then it would go back to the same noisy sound once again. Instead of simply grounding the outside of the RCA jacks, as I have heard some people doing, I took it a step further and took the amp apart. I found that the ground on the RCA jack was not getting a solid connection. So, stepping into uncharted waters, I decided to desolder the jack from the circuit board and resolder it back on with a better connection. The ground from the jack wasnt really touching the board so I took a single strand wire and soldered a 1/4" long piece of it onto the RCA jack itself and then resoldered that back onto the board. Once I put everything back together again and reconnected all the wires the noise was completely gone. I was even able to take the ground loop isolator off.
So if anyone is having a problem with ground loop and if grounding the outside of the RCA jacks on your amp seems to solve it, try this tactic. It was quite an experience for me simply because it was my first time trying any sort of soldering.
I did, however, have a little help from Meatballman, who had one prior experience with soldering. Much props to you, Meatballman, for all your time you spent helping me solve this problem!!
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