Rockford amplifier install problem...

[RacEoHolic330]

I just installed a Rockford 551x 4-ch amp for my 88 gt. when I turn the key to the accessory position, the amp works awesome. The speakers are loud and everything sounds great. But, when I start the car, there is a buzzing/ whining sound coming out of the speakers. It's louder in the rears than the fronts. When I rev the engine, the whining gets even louder. i have no idea what the problem is. Could it be my wiring? Any help would be appreciated.


-Scott

 

[grodgers]

Ground Loop most likely

I just installed a Rockford 551x 4-ch amp for my 88 gt. when I turn the key to the accessory position, the amp works awesome. The speakers are loud and everything sounds great. But, when I start the car, there is a buzzing/ whining sound coming out of the speakers. It's louder in the rears than the fronts. When I rev the engine, the whining gets even louder. i have no idea what the problem is. Could it be my wiring? Any help would be appreciated.


-Scott

Classic symptoms of a ground loop.

Where did you ground your amp?

Did you install a new headunit also?

Did you have any kind of faint whine before you installed the amp?

My 2¢ bet is that you've got an iffy ground to the amp.

Gary

 

[gruvee87vertgt]

dam-beat me to it. Rewire the ground wire to a solid part of the frame. If that doesn't work, get a noise reducer. they sell them at auto store and you connect them to the power on the radio.

 

[RacEoHolic330]

Thanks guys. I talked to other people and they said it could be the ground too. I'll check it tomorrow.

 

[CharlieHustle]

ground noise

if you wired the rca's and the power cord for the amp on the same side of the vehicle, you will get that whine noise. by this i mean along the drivers side or passenger side. seperating them will pretty much always get rid of the ground noise.

 

[grodgers]

if you wired the rca's and the power cord for the amp on the same side of the vehicle, you will get that whine noise. by this i mean along the drivers side or passenger side. seperating them will pretty much always get rid of the ground noise.

I disagree - that's a number one myth in car audio installations. The "whine" is caused by a ground loop - in layman's terms - where the same voltage applied (i.e. from the battery) will give different readings. That means you don't have a "solid ground" to the chassis somewhere.

My mustang has:

3 sets of RCA's
0 gauge power wire
Remote turn-on lead
2 sets (R + L) of speaker leads

All the above wrapped in a wire loom in one big bundle running from front to rear of the car. Alpine MRV-540 (345w rms total - benched) and Alpine MRD-M500 (591w rms - benched). I have ZERO alternator whine.

 

[RacEoHolic330]

The ground isn't the problem. I regrounded the amp to the negative battery terminal and it's doing the same thing. I'm going to reroute the RCA cables and see if that helps the situation. My problem might be because I have an alternator wire and the positive battery wire running along the side of the car and thats where I routed the RCA cables. The cables might be picking up noise from the alternator. I'll switch the wiring later and see if that helps.