speakers humming
 

hey guys.. so just recently my speakers began making a humming noise.. it gets louder as i give my car gas.. i believe its the ALT winding how do i make this stop? they are aftermarket speakers and deck but it was not doing this before with the same set up.

If they are amped the place who installed your amp screwed you over and installed the RCAs on the same side as the power. If this this is the case you need to run the RCA's ont the opposite side.

If it is not amped than your HU has a bad ground. Pull the HU and make your own ground to the chassis, be sure to scrape any paint off for a good contact.

EDIT: A ground loop isolator is also a band aid fix for this, but should really only be used if your RCAs are far from power sources and your grounds are known good clean grounds. Very rarely is that the case though.

im not trying to sound dumb, but by HU do you mean head unit... sorry im not good with abbreviations. i know its not the amp because i ran the cables on oppisite sides of my car so im guessing its the ground your talking about.

yes... HU means head unit.

Make sure both the HU ground and the amp grounds are attached to a good ground. Not every metal piece is a good ground, some pieces are isolated with rubber or paint so they are not good grounds. To make sure it's good checks the resistance between your ground and a known good ground, should be 0.00 ohms. If there is any paint between the terminal and the ground you have to sand it off and make a good contact. Since you have an amp I'd bet it's the amp with the bad ground. The HU should be wired to the original ground on the harness which is a good ground. If it is not wired to the harness then try finding a good ground.

Another thing to check is make sure your RCAs are away from ANY big wire harnesses in the car and any power wires. They could be a cheap set of RCAs that are not shielded properly either. If all else fails you can try running an RCA straight from the HU to the amp just to see if the whine goes away, without routing it through the car.

I really don't know much about troubleshooting a system so I really can't help much further than that. There may be some other cause I'm unaware of, but alternator whine is usually associated with RCAs close to a power source, or a bad ground.

RCA cables wont induce noise from power wires unless they are shielded. The shielding in RCA's can actually act like an antenna and pick up noise that would never normally be there. If youre using a simple twisted pair of RCA's then its not then UNLESS one of the grounds in the RCA's has gone bad. This can induce a nasty noise.

Check the ground of the amp(s) and make sure theyre still secure. Im inferring from your post that youve had the same gear for a while and the noise just started. If so, the first place you should look would be for loose connections.

thanks for all the help guys ill try what you have all said and let you know.