So I have diagnosed a ground loop in my stereo system causing an audible hum to come out of the speakers. Currently I have 2 amps in the left cabin storage area (where all the circuit breakers are in the fastech's). Both amps are wired to the main battery all the way back underneath the rear bench seat and grounded to this battery as well. Can anyone who has installed a stereo system in the fastech's make a recommendation for location of grounding the amps?
My ground wire going all the way back to the battery is almost 15-20 ft long and causing a pretty bad hum.
Anybody have recommendations for amp locations in a fastech?
I was thinking of relocating the amps to inside the storage area under the rear bench seat but am a little worried of this area getting wet and causing some electrical problems with the electronics.

what size wire is the feed and return, my amps are that far away and dont have an issue.

The grounds are best run directly to the battery. The size of the wire should not matter as much as the quality of the grounds as far as noise is concerned. Also make sure your RCA's are of good quality and 100% sheilded. DO NOT coil up extra RCA wire if at all possible. The coil acts like a antenna for noise. Other then that I have seen a number of times bad circuit boards on amps cause noise. That one is tough to figure out. Some times just a different amp from a different manufacturer can do the trick... Noise problems can suck to get rid of.

9 out of ten times, a ground loop isolator worked for me.

http://www.radioshack.com/product/in...ductId=2062214

It could def be that my amps have gone bad. I have bought replacement amps, just haven't had time to install yet. The power and ground cable are size 0 wire and of good quality. I do have about 7 feet of co-ax cable wound up that is running into my mono-amp which could be causing the problem. I will probably be purchasing all new wiring and cables for the 8 speakers and new cables for the connection between stereo and amps. Hopefully this would solve the issue.

What kind of speaker wire did you run and how is it run. You want your speaker wire to be twisted not flat. The twists help to reject noise. If you have 7 feet of RCA wire coiled up then it is easy to unwrap it and see if that fixes your issue.

I honestly have no idea what speaker wire is run to the speakers. I hired a guy to come in and fix my stereo last summer but by the looks of it he just bridged a lot of things and told me I had bad amps. However the buzzing was a lot worse after his work than before. I have bought all new twisted oxygen free speaker wire in 16g and 12g to run to the subs and speakers. I have 2 new alpine amps that I am going to install along with new RCA cables and a new head unit...basically a totally new stereo system except for the polk 6x9 front speakers. Should be fun to install. I am going to try to keep the amps grounded to the battery and see if the buzzing goes away with all the new equipment. Keeping my fingers crossed.

+1...for me grounding amps and head unit direct to battery solved all noise problems

I used the same gauge and quality cable for both + and - from the amp to the battery. Be sure to use the right size cables for the length you are running. Cut to length, no loops. Do not run speaker wire along side your power cables. I use one battery for the stereo only, not sure if that makes any difference.
You should be happy with the Polks and new power.