Culprit for HU noise?

[Team Hammer 10+ year member]

If you are using a Pass Through RCA Cable to the other amp, I bet the gain is to high on the first one.

Seen this before.

 

[ratedrookie 10+ year member]

Is it only from one amp ?

When I disconnect the RCA cable from either amp, then yes, the noise does go away. Once I plug the RCA's into both amps the noice comes back.

If you are using a Pass Through RCA Cable to the other amp, I bet the gain is to high on the first one.
Seen this before.

If by pass through RCA cable you mean having the RCA cable run from one amp's output to the other amp's input, then no. I have a RCA cable connected to my HU's front speaker output to one amp and the other RCA cable connected to my HU's subwoofer output to the other amp. I have the remote wire daisy chained from one amp to other if that matters.

As far as the gain settings are concerned, I haven't touched them since first installing the system over a year ago and never had a noise problem until recently. I tried turning both of them down to see if it would help, but didn't impact the noise issue at all.

 

[Team Hammer 10+ year member]

Try routing the RCA cables somewhere else away from any power cables, Would be my next try. If not try a new set of Good RCA cables.

 

[supa_c 5,000+ posts]

he already did that....

 

[ratedrookie 10+ year member]

Try routing the RCA cables somewhere else away from any power cables, Would be my next try. If not try a new set of Good RCA cables.

I have both RCA cables, remote wire, and HU ground wire running on the opposite end of the power cable. I have also tried a different set of RCA's with no success.

I found this chart:

http://www.crutchfieldadvisor.com/ISEO-rgbtcspd/learningcenter/car/noise_diagnose.html

and following along my answers would be No -> No -> Yes -> Yes.

According to this chart I need a power line noise filter, but if there ever was a problem wouldn't I have had the noise and the need for a power line noise filter from day one of the system install and not almost one year later?

 

[supa_c 5,000+ posts]

radio shack has those for cheap

 

[ratedrookie 10+ year member]

I did some research and talked to a few stereo shops and they all said that a power line noise filter is only for when the noise increases/decreases with engine speed or if the noise is consistent with all music. The noise I am hearing does not depend on the engine speed and is not consistent with all music.

The noise I get is only in some songs and not others. I'm at the point now where I am almost ready to give up trying to find the source of the noise and just learn to live with it.

Anybody have any other ideas?