Strange whining noise?

[325is_MadBimmer]

Ok so my system sounds great and all, and i am satisfied with it, but there is this whining noise.

This is what happens, my headunit is off and my car is idling, its all fine, i rev it its all fine.

then i turn my headunit on and all of a sudden there is this whining noise at idlea and when i rev it gets louder, Unless the volume is low, i cant hear it.

I can only hear it inside the car so i am pretty sure the noise is going through the speakers.

[KenC]

Your power cable is too close to your RCAs. It's 'alternator whine'.

[Matto]

Or your ground isn't hooked up right.

[325is_MadBimmer]

Your power cable is too close to your RCAs. It's 'alternator whine'.

my amp is on the left side of the trunk, and my ground and power are hooked up to the battery. How can i try and fix this?

[KenC]

Your power cable is too close to your RCAs. It's 'alternator whine'.

my amp is on the left side of the trunk, and my ground and power are hooked up to the battery. How can i try and fix this?

Don't ground it to the battery. Scrape the paint away inside your trunk somewhere and use a ring terminal with a self-tapping metal screw and screw it right into the body of the car. Make sure the ground is no longer than 18" long.

Are your RCA cables (the signal cables) ANYWHERE near the power cable? If the whine is changing pitch while your engine revs, it's coming from the alternator. You need to move the power cable as far away from the RCAs as possible.

[SpeedDemon_e30]

And has he said before. Check and make sure the batt wire is not next to the RCA wire. Make sure that your batt wire are not nex to you Speaker out put wire as well..

[EverWiser]

As a rule of thumb in the electrical world, if you have power and signal (in your case the RCA's) wires in close quarters, try to run the signal wires at a 90 deg angle from the power wiring. If you run them parallel, the magnetic field around the power wire(s) will induce current in wires ran parallel to them (the whine your hearing). As you rev higher, your charging output from the alternator goes up causing the mag field around the power wiring to increase thus inducing more whine in your signal wiring. The more current in the power wiring the greater shielding and/or distance you need between the wires. If they're at 90 deg to each other the mag field from the power wire is only acting on one point of the signal wire and therefore doesn't "induce" the noise. I hope this helps.

[325is_MadBimmer]

Your power cable is too close to your RCAs. It's 'alternator whine'.

my amp is on the left side of the trunk, and my ground and power are hooked up to the battery. How can i try and fix this?

Don't ground it to the battery. Scrape the paint away inside your trunk somewhere and use a ring terminal with a self-tapping metal screw and screw it right into the body of the car. Make sure the ground is no longer than 18" long.

'

Well i regrounded my wire and the whining noise is gone. The ground cable was so long before, i didnt think it made a difference, i cut it to about 16 inches, re grounded it and its fine now.

thanks

[325is_MadBimmer]

Your power cable is too close to your RCAs. It's 'alternator whine'.

my amp is on the left side of the trunk, and my ground and power are hooked up to the battery. How can i try and fix this?

Don't ground it to the battery. Scrape the paint away inside your trunk somewhere and use a ring terminal with a self-tapping metal screw and screw it right into the body of the car. Make sure the ground is no longer than 18" long.

'

Well i regrounded my wire and the whining noise is gone. The ground cable was so long before, i didnt think it made a difference, i cut it to about 16 inches, re grounded it and its fine now.

thanks

I take that back, then whining noise is back again. I think it will make it a lot easier for you guys to determine this after i post some pics tomorrow night.

[Alluvium]

i have the power cable running along the left side skirting ect, and i have my rc cables running done the middle under where the hand brake is (on left hand drive cars i think maybe the wires come in on the right side by the cubby...so run power down the right side of the the car, under the abck seats and into a hole to the boot)... any way i was messing around with the pannel next to the cubby ..and i pput it back together and got the DEATH WHINE !!! da da daaa

turns out i ran the power cable oevr the crossover for my right side tweeter... doh... check out for this if you got tweeters.

[cunninglinguist]

Strange whining noise?

Punch whoever is sitting in the back seat and be done with it.

[BMWguy]

How do you guys recommend running the RCA's... down the middle or down a side in an E30? Wont this affect/cause a whine sometimes? I thought I remembered reading it in a thread somewhere...

Also wont running a capacitor inline with the power/ground help reduce engine noise?

[808BMW]

How do you guys recommend running the RCA's... down the middle or down a side in an E30? Wont this affect/cause a whine sometimes? I thought I remembered reading it in a thread somewhere...

Also wont running a capacitor inline with the power/ground help reduce engine noise?

I prefer the middle strictly for cleanliness.

No a cap will not reduce engine noise. Cleaning all your grounds will.

[BMWguy]

I prefer the middle strictly for cleanliness.

No a cap will not reduce engine noise. Cleaning all your grounds will.

Thanks Bob... thats how I did mine... just wanted some reassurance :up: