Amp Question

[audiobahnkid592]

I have alternator moise in my new car with system from my old car (noise was in previous car but not as bad.)

i'm having issues with alternator noise in my 2009 cobalt. i just ordered new RCA's thinking that might be it since that is the last thing i can think of besides the inside of the amp. the rca's on the inside of my audiobahn a6004t amp run from the bottom right corner to the top left corner. could the wires crossing over the power lug create my whinning noise? of am i way out of line?

[tsmith1315]

Unless there was some damage (broken solder joint, etc) when swapping the amp, the problem isn't likely to be internal.

Damaged RCA's are a real possibility, unplug one side at a time and see if it dissappears.

Most likely it's a ground loop, that's the source of the vast majority of alternator noise issues in cars.

What other components are in the car, what HU are you using, and where are they all grounded?

[Perry Babin]

If the noise is really bad, you may have an open shield ground on the head unit.

If the noise isn't significant, the RCAs could be picking up the noise from parallel wiring. Before you run your new RCA cables under the carpet, run them over the seat or outside the vehicle to see if the noise is eliminated or significantly reduced.

[audiobahnkid592]

Sorry for the late response the noise is only truley audible on vol 5 or lower. i did run a set of rca's from the head unit over everything to the amp and the noise was almost 100% gone so i know its that. its dead quite with no rca's hooked to the amp. i did order a set of moster cable 4 ch rca's that are claimed to be quite good cables so mabe that will address my issue.

[jol50]

Keep the RCA away from the power if you can, however I swapped amps lately and one had whine and one does not with no other changes. My RCA is near the power in a couple tight spots, but I ran various other amps in the last system in this car with no issues. I ran anther better quality RCA for this because I needed another is only change to them....and got rid of RCA to an EQ that was mounted in the console/shifter area and wired from under the seat. You may be able to move the RCA and find the place it does it if you can expose them.

[amc32]

Isn't the whole car (chassis) a power wire. Ground has potenial too?

[Perry Babin]

Anything that has resistance (even if the resistance is minimal) and current flowing through it has potential across it.

[0ldSch00lf00l]

Technically, every metal piece in the vehicle is a ground.

[Abob89]

Whenever I do an amp install at work that will be playing anything above subwoofer frequencies* I always run a source ground just in case, even though I always run the power down the side that the battery is on and the signal on the opposing side of the car you can never really be too safe. I understand that running source ground is a bandage if there is any noise in the system but it is a little extra insurance that the job will be done right the first time.

*I have seen people's cars come in with noise in their sub outputs. However there were typically extenuating circumstances as to why their equipment had issues. In the 2 cases I have witnesses there were actual equipment failures.

[audiobahnkid592]

my cables are probally a foot to foot and a half away from the power wire. they cannot be moved either