Engine whine from speakers

[sideswipe]

I just had a cap installed and a new speaker box. And now I have this whining noise at all levels (more prominent if the volume is lower) that is coming from my speakers (door speakers it appears, but im not sure if its the subs too). I took it back to the shop that did the install and all they could suggest was a noise filter. Any ideas where to look first. I really dont know much about car audio installs so try and keep it simple for me. I didnt have this noise before the cap and new box were installed. Thanks guys.

 

[jimbo74]

it is speaker noise..... there really is no cure for it... just some quick fixes..... explorers have really bad rfi.... meaning it is the amp or receivers fualt not the speakers... try to run power directly from the battery. make sure your ground is good... install a filter....

 

[leenjen]

there is a very simple cure for it. run the power wires and the speaker wires/rcas seperately. the electrical current from the power wires is causing the whine in the speakers. if the wires touch or are very close, this sometimes happens. another cure for this is to buy better wires that are shielded better, but that's a lot more $$. dont go with the noise filter. they cut down on the output of your speakers, and they usually burn up in time. just re-route the wires and you'll be fine.

 

[sideswipe]

The weird thing is, all they did was add the cap and change the box, they didnt run any new wire along the moulding, and the noise wasnt there before. Could there be wires touching in the back where the box/cap is somewhere?

 

[leenjen]

that is strange.

your capacitor is only on your subwoofer amp, right? it shouldn't have anything to do with the full range amp, so they shouldn't mess with it. maybe they did move a wire or two just enough for it to pick up on the current from the power wires.

 

[sideswipe]

Yes I beleive its only hook to the sub amp, but the cap itself sits very close (physically) to the amp that i have for the highs. Also, if i remove the RCA cable for the speaker that are in the doors, the sound goes away. So I'm guessing that the sound is only in the door speakers. I wish I knew more about car audio! arrgh!

 

[KEbert]

As far as I know, anytime you have a capacitor that does not have a ground, you will get interference in your stereo. I may be wrong cuz I don't know much about caps.

 

[99explorer5.0]

You said when you move your RCA cables the sound goes away ... go out and buy some quality RCA's that are sheilded. If what you said was true that should solve your problem.

 

[leenjen]

Originally posted by KEbert
As far as I know, anytime you have a capacitor that does not have a ground, you will get interference in your stereo. I may be wrong cuz I don't know much about caps.

a capacitor that doesn't have a ground????

never heard of it. how would it work?

 

[sideswipe]

The problem only goes away when i disconnect the RCA sbecause that disconnects the speakers. It doesnt seem like its a cheap cable issue.

Originally posted by 99explorer5.0
You said when you move your RCA cables the sound goes away ... go out and buy some quality RCA's that are sheilded. If what you said was true that should solve your problem.

 

[EO]

I'm assuming you just got a new speaker (sub) box, and kept the same subwoofer. If that's the case, then the only thing that changed electrically is the addition of the cap.

Take your ride back to the shop and have them temporarily remove the cap. Then play something at low volume and see if the noise is gone. If so, then you know the cap (or associated wiring) is it.

If the noise is still there (and it wasn't before), then it gets a little more complicated because they changed something else during the install that's not so apparent.

As many have said, power wires alongside RCA/signal wires invite noise. Possibly the cap was wired near RCA/signal wires? The fact that the noise is coming through your door speakers is maybe irrelevant; it's just new noise in your system that manifests itself in that location.

Good luck; let us know what you find.

 

[DocVijay]

Change the grounding spot.

It's a ground loop problem. Change the place where you attached the ground and it should help. I used to have one in my other truck. Whenever I stepped on the brakes, the sub thumped. It was really strange.

 

[JTang]

Sub thumping like that is supposedly common in certain cars, like BMWs. Don't know the full deal, but it thumps cause of RFI with the brake lights or the relay directing them. Just thought you guys would like to know - random car audio trivia...

 

[DocVijay]

Change the grounding point.

Sometimes, if you simply change where the amp(s) are grounded, it will reduce or eliminate thump and/or whine. Get a longer bit of ground wire and get as far from any electrical equipment as you can. It get rid of mine in my truck. They also sell ground loop isolators (at Radio Shack I believe) that plugs in inbetween the head unit and amp.