Okay I got my 4 channel MTX amp hooked up today to my front/rear speakers and they sound ******* great...but I have a small problem

when I started driving I noticed a little whirring/high pitched noise and i turned down my stereo and it was more apparent. It only happens under these conditions:
1. Car is running, if I rev up in neutral the pitch while go higher in tone just like the engine
2. When I'm going through the gears and I have my stereo/amp on it is the same as #1.

when I have my car off it doesn't happen..has anyone had this happen to them? Or have any ideas? I mean I paid 400 for the amp/install I wasn't expecting this cuz it could get annoying real quick if I'm not listening to my stereo. Thanks

 

Alternator noise. I have the same thing. Funny thing is some times it is more pronounced than others. I have tried to eliminate it but have been unsuccesful so far.

Make sure that the main power lead running to the amp does lie near the RCA cables.
Check all grounds. Make sure they are metal to metal connections and are run with the appropiate sized cable.

I've heard of antenna interference too, but I'm not quite sure how to remedy that aside from maybe an in-line noise suppressor.

 

ya I called them today and that's what they told me. I'm taking my car in tomorrow to get it fixed hopefully, thanks for your reassurance. It's just really annoying when my stereo isn't on and Im just trynig to talk to someone in the car or on the phone.

 

If you paid for it to be installed, march right back and tell them to fix it. They didn't install it correctly if you are getting alternator noise.

Generally, it's a bad ground that causes this situation. Typically I have found the RCA cables to be the culprit only if they are either defective or really poor quality.

Just make sure both the head unit and the amp(s) are well grounded. That's definitely where you would want to start.

 

its alternator noise that your system is picking up... I've never installed a system that had noise (and I don't work in a shop or anything)... anyway its alternator noise/interference... since you paid to have it installed I would take it back to the shop and complain about it.. it is either they didn't separate the power and RCA/speaker wires and just bunched and zip tied them together or their in close proximity of each other, or you have a bad ground (not metal to metal contact)..

well since its a shop that you paid to install... I would take it back.. but if you wanted to check yourself.. make sure its grounded on bare metal (not a painted surface).. make sure the head unit is also grounded on bare metal.. and make sure the power wires are not run w/ the speaker wires.. also make sure that they didn't use cheap RCA cabling and that its shielded and for car audio applications.. they should fix it for you for free.. good luck

 

yeah, i used to be cheap and not buy the 30 dollar RCA cables, i usually could make it work with little to no noise just by makeing sure the power and speaker wires were seprate. but those 30 dollar RCAs make it 50x better