Opus

I finally got around to adding an amplifier to my car, but I'm having some problems getting rid of background noise. I have some static in the background whenever the radio's on, whether the engine is running or not. And when I accelerate I hear some crackling sound.

It's a Pioneer 400watt amp with the factory head unit in an 02 P5, using speaker level inputs. I have Infinity Reference components up front, Reference 6.5" in the rear. I used an amplifier install kit, spliced into the power-antenna wire for the turn on signal, and grounded to that empty bolt hole on the left rear drivers seat post. I cleaned the paint around the ground with a Dremel, so it looks pretty good.

Anyone out there have an idea where I should look to solve this problem? Also, since I'm amplifying the factory head unit should I expect some background static no matter what?

Thanks for any help

hihoslva

What power antenna?

As far as I know, no Protege ever came with a power antenna.

I would first choose a different remote wire location - you can tap right into the fuse box if necessary, and find a switched source. I'm not even sure how your amp is powering up, because I'm not sure how your remote wire is getting voltage.

I think this would be a good starting point. Change the remote wire, and let us know what happens.

~HH

DaleK

There is an antenna out on the factory deck - believe it or not. It may only turn on when the radio is playing (and off when the CD is playing). At least that's what mine does.

I'm with Hiho - try another remote turn on location. I used the ignition lead from the car to the deck on mine.

Also, where are you connecting your main power wire to? Is it direct to the battery? If not, you might want to consider doing so.

Dale.

Astral

Check this FAQ, section 2, it gives you step by step instructions for determining where the noise is coming from in your system.

For example, to see whether it's the amplifier and/or the speaker wires, you can make some muting plugs to plug into the amplifier. That way, the amplifier is getting "silence" for a signal, and you'll hear any noise induced by the amp or the speaker wires. If you do that and don't hear any noise, then your amp & speaker wires are OK, and the noise is coming up from the rest of the system (read that FAQ for more).

I had to build a muting plug the other day, it's real easy. You're just shorting ground and signal. Go to a local Radioshack and in those little part bins, they sell solderless RCA plugs. In those plugs, you pull the ground wire thru a small hole and crimp it and for the signal wire, you wrap it around a screw and screw it down. So, just take a small piece of wire, pull one end thru the ground hole and attach the other end to the screw. You should now have a perfectly shorted plug.

Opus

I am running directly off the battery, with 8-gauge wire and fuse. I tried running the turn on lead directly from the battery also and the static is still there.

Thanks for the troubleshooting website, I'll try that this weekend. I'm using speaker level inputs with the factory head-unit, but I assume those muting plugs can be made the same way with short lengths of speaker wire.

I'm using crimp-on snap together connectors for my wiring. Could that be causing some problems? I'd prefer not to solder in the car, I'm not too skilled. I sealed the ends of the crimp-ons with electrical tape and made sure no metal was exposed.

Aydu

I have 2 amps in my 02 Sedan. No noise, great volume and clarity.

I am using a high quality loc instead of the speaker level inputs on my amp.

I got more noise - alternator whine - with the speaker level leads. I could eliminate the noise, but then the volume I wanted wasn't there. The LOC is adjustable and gave me both.

The noise you are getting is different. I read in another post that you tested the factory head unit outside the car with a separate battery and still got the noise. If you used test speakers - not the car speaker wiring - I'd say the noise is in your head unit. The amp you added may just be boosting it to a level you can hear.

djs2571

I'm having an issue with a blaupunkt class D amp, whenever I turn it on, the FM seek finds nearly every frequency as a station. And I get reduced reception quality when the amp is on... turn it off and everything is great. There does appear to be an antenna amplifier somewhere, though it's not shown in the factory wiring diagram
But if your just getting noise when the radio is on and not a CD/tape this amplifier may be picking up noise.

vw2p5

are you using an FM modulator for the amp?

vw2p5

are you running the power wire and the RCA's down the same side of the car? is so try running the power and the RCA's down on seperate sides of the car. using those speaker inputs could cause the noise as well, trying going with a aftermarket head unit. As far as the power antenna wire goes, you are suppose to use them to turn the AMP on and off, that should be fine.

djs2571

You can try a ground from the battery, to the radio grounding point, then to the amp... that would reduce any voltage drop that could be inducing noise. Is there more noise when the system is turned up? That could clue you into a voltage drop problem, I was never a fan of using chassis ground for a high current device.

I think the FM modulator question was for my previous post, and no, line level adapter to the amp and just running a sub. I put an oscilloscope on the power lines and found tons of noise just when the amp remote lead is turned on. Trying small caps (0.1uF - 10uF) as well as a 0.25F cap across the power leads made no difference in the noise on the FM radio or scope readings. But CD's sound fine - I am planning to switch the amp off when not needed cause it's just there to fill in the low end below what the stock system can produce. And that'll be fine in my situation, though i'll likely swap in a different amp to fix the noise issue. I was suprised that just the amp was making up to a volt of noise in the megahertz range - ugh.