Need help finding cause of noise.

[Radioflyer97 10+ year member]

Need help identifying Noise in my system:

The setup:

Alpine IVD D310 head unit

Alpine PXA H701 Processor

(2) alpine MRp F250 Amps running briged (one amp is front one amp is rear)

All Amps are powered and grounded through a common distribution blocks and grounded at the seat bolt (nearest solid ground)

The noise remains constant at all volume levels and continues even when the source unit, auxillary cooling fans and processor are disconnected. Engine running or not does not affect the noise.

Here's a sample of the noise I recorded:

Click to read more...

 

[Ineed$ 10+ year member]

what's that noise?

 

[thevic24 5,000+ posts]

that kinda sounds like a bad rca ground. could eather be the cable or the jacks at the amps or hu. un plug the rca's and if the sound goes away, your problem is somewhere in the cable, jacks, or signal source.

 

[kovemaster559 5,000+ posts]

interference or rca's is my guess

 

[Radioflyer97 10+ year member]

that kinda sounds like a bad rca ground. could eather be the cable or the jacks at the amps or hu. un plug the rca's and if the sound goes away, your problem is somewhere in the cable, jacks, or signal source.

For the time being, I think i know what happened: I originally had a CDA 7998 which has 4v Pre-outs. During my swap, I got the IVA D310 in the mail first and installed that and removed the ERA G320 and sold it and the CDA 7998. I tuned my system to the IVA D310. Then the PXA H701 Arrived, I installed it and re-tuned but forgot to adjust the gains on the amps back to 4v pre-outs.

The noise is still there....but significantly less. I'm looking into a set of Pac SN1 noise filters as a permenant solution.