help w/ engine/ignition noise
 

I've recently been having problems with alternator whine (usually only at night w/ the headlights on) and some type of buzzing, popping, lower pitched noise (random intervals) which seems to be ignition noise according to some faqs I read online.

Here's my set up:

Kenwood Z828 mp3 head unit
Phoenix Gold T400.4 amp
Infinity Kappa 60.3 front seperates
JL10W3 sub
1F capacitor

At first I thought it may be a grounding or wiring problem but the power and signal lines are routed on opposite sides of the car and the grounds seem to be ok. Also, it's always on ONE speaker; if I switch the left and right inputs to the amp, the noise will switch to the other speaker. I haven't gotten around to switch the outputs from the head unit yet because I don't have the little tool that they use to pull the head unit.

If this were a wiring or grounding problem, I would think it should affect all speakers since all the signal wires are routed righ next to each other right? I think the problem is likely somewhere between my head unit and amp because the noise switches sides if i switch the inputs but I would like to get more input from you audio guys out there before taking everything apart... I'm hoping I don't need a new amp or head unit but after reading some posts on usenet, the problem seems to be pointing at my amp. I was thinking of changing my plug wires but again, I would think if that were the problem, both sides would pick up the noise and it wouldn't be isolated to only one speaker.

Recap: intermittent engine/ignition noise only on ONE speaker... if I switch the inputs to the amp, the noise also switches over to the other speaker. Any help would be GREATLY appreciated, thanks.

All I can say is go over your wiring again. Use quality wire, solder every connection, and ground everything in the same spot!

If you go over everything and it's still doing it, run the power from the amp that's now going to the one buzzing speaker into another speaker. If it still buzzes, then it's something probably in the amp itself, or the output of the headunit.

I can't stress enough how important good clean wiring with solder connections is.

The installer used Phoenix Gold wires/RCAs, but interestingly enough, one RCA connector on the amp input was soldered very poorly and fell right off when I tried to pull the connector off the amp... I guess it could well be that the connector on the other head unit side is poorly soldered as well. Thanks for the input... I'm not really much of an audio guy but I guess I should try pulling the head unit myself so I can see how the wiring was done.

I hate Phoenix Gold RCAs. They are very cheap and always pick up noise. Your cables are more than likely the problem. Head units almost always work. If you unplug inputs and all noise goes away then you have verified amp, speaker wire, and speakers as NOT the source of noise.

Look to buy some other RCAs. I like Monster cable and Lightning audio cables myself.

I have an old school Infinity Kappa 102a amp that is bridged temporarily to power my interiors and I have "road noise" through the speakers. I know it is the amp that is doing it because I hooked a different amp up and it doesn't have the noise.

Long story short, try a different amp. You gotta have a friend who you can borrow one from. This will definitely tell you what it is. Like spyfish007 said, head units are very seldomly the problem.