I'm new to the forum so, hello all.
I have had a nasty alternator noise problem for about two weeks. I'll try to make it short.
My setup in a 2002 Silverado is: Alpine CDA-9815 to a PG Tantrum 400.4 (running Infinity comps.) The sub amp is a PG Tantrum 300.2 running a sealed 10" Tantrum sub. KnuKonceptz RCAs and Collosus cable.
Setup ran great for 3 years. I only ran half of the 400.4 for the fronts until the gain knob developed a short. The other half always had alternator noise so I never used the rear channels. To avoid replacing amps (because i'm not real deep in the pockets) I swapped the amps. The good half of the 400.4 now runs the sub and the 300.2 runs the comps. Problem: I now get alterntator noise out of the 300.2.
I have done the research, google, search button and all that stuff. Been trying to problem solve for three nights in a row. Did the "big 3", grounded the HU to the chassis, even ran another ground from the frame, to the body near where my amp ground is. I KNOW my wiring is golden because I tested it with a VOM!! Power wire is on the opposite side, etc. I tried grounding the RCA cables at the HU and the amp. Still noise!!
Noise is on one channel, regardless of what side of the RCA I use.
I unplug RCA @ amp, noise goes away.
Unplug RCA's @ HU and noise is still present. I used mute plugs @ amp and noise is gone.
I ran a different RCA directly from amp to HU and still got noise. Got noise with that same cable unplugged from the HU.
This is only the case on the 300.2. Ran same tests for the 400.4 rear (because I always had alt noise in those) Alt noise waaay louder. Run the mids to the front on the 400.4 and no noise but the shorted gain knob causes noise and unbalanced, distorted volume in the comps. That amp is getting replaced soon w/ZedAudio.
I think I might have a bad HU because of the signal from the HU. Or maybe another bad amp? Is there something I missed here?
Calling all experts for help...
Please help
