Still getting alternator whine after a year.

**Maheriano** · 03-07-2007, 11:09 PM

So I've made it a year with a carputer and haven't burned my car to the ground yet. Who knew. Anyway, I've been getting alternator whine in my speakers and figured it was because of the location of my speaker wire near the power wire that I didn't post the question here before. So I kept the power wire running under the door sill and moved the speaker wire into the ceiling/pillars to separate the two completely. For some reason I am STILL getting the whine and it gets higher pitched when I push the gas. How is this possible? I'm using a ground loop isolator on my front and rear channels with the isolator on the amp side. Here are specifics about my setup:

- m10000
- M1-ATX
- no headunit
- speaker wire coming from speaker wire in dash to 4 channel amp, through ground loop isolators (front/rear) into on board sound.
- subwoofer RCA cable has no ground loop isolator
- M1-ATX getting power straight from battery via 10 gauge wire
- M1-ATX grounded to bare metal frame along with both amps at same point.
- 4 gauge wire coming from battery to distribution block, 2 8 gauge wires going to amps

Need to know anything else? It's a 2005 Civic and shouldn't have any electrical problems. I searched for answers but most of the threads deal with power wires and ground loop isolators.

**2k1Toaster** · 03-07-2007, 11:17 PM

Originally Posted by Maheriano

So I've made it a year with a carputer and haven't burned my car to the ground yet. Who knew.

I literally lol'ed at that! Thank goodness that you are getting power straight from the battery instead of the cig lighter!

But have you made a little ground from a motherboard standoff to a ground? That might help a little bit.

**Maheriano** · 03-08-2007, 12:25 AM

I'm guessing no since I don't know what that means. Is there an explanation somewhere on how to do this? Is it just wrapping a wire around one of the motherboard spacers and running the wire to a ground?

**2k1Toaster** · 03-08-2007, 12:29 AM

Originally Posted by Maheriano

I'm guessing no since I don't know what that means. Is there an explanation somewhere on how to do this? Is it just wrapping a wire around one of the motherboard spacers and running the wire to a ground?

yes

**Griff1** · 03-08-2007, 04:07 AM

the order in which you ground your devices is key here,if they're all grounded to the same point its important to have the item pulling the most amps grounded first then the next highest after that and so on.

If their not all grounded at the same place then that could also be the problem.

You should also keep the earth's as short as possible,in my Zafira all grounds are in the boot,together on 1 point and i have no whine at all.

I use an M2-atx and have 2 amps totaling 600 watts.

Its strange as i've only ever used ground loop thingy's when running from an invertor.

**Maheriano** · 04-24-2007, 03:46 AM

Finally fixed this 2 days ago. I had ground loop isolators on the front and rear RCA cables. Once I removed one of them and used just a regular RCA cable the whine is gone.
Plus about a month ago I re ran the speaker wire along the headliner and away from the power cable but at the time it didn't change anything.