AUDIO EXPERTS! Very Annoying Alternator Whine thr Stereo.

SON240sx Automotive
1

Ok, for the life of me I can’t seem to figure this out…

I have a Kenwood 428 deck hooked to an Alpine F407 amp. The amp is directly connected to the battery + and - which is right beside it in the trunk. The ground cable is shorter than the + and less than 18".

When my car is off, the system sounds fine… maybe a tiny bit of hiss/distortion which could be normal, but when the car is on, i get a high pitch whine which varies with the speed of the engine. The volume of it does not change however. So cranking the stereo usually masks it.

So from what I read it appears to be a ground loop… And I don’t know what else to do!

So far I’ve:

Replaced the Deck.
Replaced the Amp.
Run an ipod through the rca wires the stereo uses to check for bad wires.
Tried multiple grounding locations, (Stereo harness, antenna, battery, hole drilled in frame under the stereo.)

If I plug an ipod or device straight to the amp, it gets rid of the whine and distortion. So I thought it was the deck since it was an open model… but replacing it didn’t help.

The RCA’s are going to the amp, and i’ve hooked all the speaker wires on the harness up even though they’re not really doin anything…

Now originally the unit wouldn’t power on when i connected the ground via the factory harness. Only when a hole was drilled in the frame, or antenna plugged in would it come on. Could my car have some major grounding issues? (Passenger window doesn’t work, heat gauge bounces, car stalls after putting clutch in at high revs, alarm acts funky etc)

What I dont get, is if it was coming from the deck or wiring at the deck, would the whine not be amplified by the amp?

VERY CONFUSED!

James

:? :? :? :? :? :?

2

I have the same problem with my iPod :frowning:

I use an AUX cable to hook up my iPod and anything about 3000rpm+
I will hear a high pitch whine (and its pretty much in sync with the throttle/RPM).

I have a ground loop isolator as well.

I’m curiuos on how to resolve this issue as well. :sadwavey:

3

Well using my ipod thing through the stereo’s aux gives me the whine…only testing by hooking it right to the amp it doesn’t. I’ve also bought a noise filter thing from CT, but it made no diff…

James

4

Ive had this issue with the new mazda 3’s. U cant put a deck in this car as theres no company that makes an indash…unless u stuff ur deck under a seat or sumthin and leave the factory indash alone. U get that really high pitched whine. we installed isolators which got rid of some of the noise. the more u pay for isolators the better they will work dont go cheap on them. make sure your running high quality rca cables and their away from any power wires. i run my rca wires down the drivers side and everything else on the passengers. if at all you haaave to cross sum other wire dont follow the wire cross strait over it making a t or X. it doesnt seem like it has anything to do with the amp and its wiring…possibly try running the power wires for your deck strait to a battery in your car drive around the block see if it solves the problem…if it works run a ground wire to the deck from your cars batt as well as a live wire. then find a new source for that yellow power wire i belive it is…find it at the fusebox making sure its only live when the cars in start position…or u can run it to a live wire and wire it to a switch so when ur buddys want to stay in the car u dont have to leave the keys with them and worry about them taking ur 240 out for a spin…cuz most them drive fwds and its temping. only downside is u gota rem to turn the switch off or ur deck will continue to play and run ur batt dead. But deffinatly make sure ur RCA cables are away from any live wires and try running pos and neg wires from ur batt to ur deck.
-Devin

5

Ok, now I feel really dumb… just before I posted this I searched on another forum for someone who had the same prob… I didn’t think it would fix mine so I posted anyways… Well on my next trip the the car I try adjusting the levels on my amp…the gain in peticular (which was maxed), put it back to normal and guess what! I just realized I wasted about 5 hours of my life… Thanks guys…

6

Hahahahah way to Go James

next time just call me :smiley:

7

u need better grounds

8

Do you have the power cable of the amp running along side with the rca wires that run from the deck to the amp? If so this will cause a high pitch whine from the motor. Run the power cable along one side of the car and the rca cables down the other side. That should fix the problem IF that is the situation.

9

ditto that keep the audio signal wires away from everything else electric, also, try getting a voltage stabilizer, that might help

10

Oh, I sorta fixed this awhile ago… The RCA’s and the power WERE going seperate sides of the car. And plus I had run the rca’s straight back over the seats to see if there was a diff. It’s when I was playin with my amp settings that I realized my GAIN was too high and causing the whine. Once I put it back to the normal level the whine is pretty much inaudible as far as I can tell… Man… all that after I replace the deck, rip out the wiring several times…replace the amp etc… it’s the freakin GAIN… I’m more mad nobody suggested that and put me through all that greif !! :stuck_out_tongue:

James