Noise problem

[LZC8114 10+ year member]

Got everything connected up only to hear some humming in the speakers(volume all the way off) and alt noise when engine was on( noise changes with rpms). Been searching through the archives and did these tests so far. RCA's and power wire on opposite sides of car.

If i disconnect the amp for the front componet speakers it goes away.( sub amp still connected and back speakers hooked up to headunit still working fine)

- Switched rca's with the sub amp but didnt do anything

- Took out rca from the back of the componet amp and noise went away.

- Plugged rca's back into componet amp and unplugged rca's from the headunit side = noise still there.

- regrounded amp but didnt help.

Then to make things even more wierd i had the speakers all up and running last week( no sub or sub amp in) and had no problems.

Not sure what it could be, any ideas or more tests?

thanks, LZC

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[dkguitarist 5,000+ posts]

try running a straight ground to the battery and see if that helps. also, "ground" the rcas to the hu (via a piece of speaker wire).

 

[da12b 10+ year member]

You have what is called "Alternator Wine." I also have that in my car as well as my other car, which is now history. Sold it. I had connected the cont. and the power wire of the head unit to an 8 GA cable and directly to the pos. terminal of the battery (make sure it is fused with the correct fuse rating for the wire/cable like the power cable to your amp). The noise was gone -OR- barely audible. I will do the same with my current ride.

The reason for this is due to the fact that the cont. and power wire wired together is thicker then the OEM power wire. Therfore it will have feedback. (Feedback is the "Alternator Wine.")

Before you go out and buy a bigger GA. cable, check ALL OF YOUR GROUNDS first. It might just be the problem.

Hope this helps.

 

[johnecon2001 5,000+ posts]

It's going to be some sort of grounding issue. Either RCA related, Amp related or HU related.

Get yourself a multi meter that measures ohm loads. Find a grounding point that has closest to 0 ohms as possible.

 

[jrz126 10+ year member]

The reason for this is due to the fact that the cont. and power wire wired together is thicker then the OEM power wire. Therfore it will have feedback. (Feedback is the "Alternator Wine.")

That makes no sense and has nothing to do with the noise.