Audio Systems: Static, impulse noise, aftermarket installations

Question
I am experiencing static noise when engine is on only at a low volume. When
engine is off no static noise. I have installed, pioneer 6800 CD Deck,
soundstream preamp, one direccted dclass 2400. one soundstream 720, one
soundstream 480, 2 pioneer for subs, 2 8" m and n's for mids, 2 6 x 9 and 6"
also for mids and two batteries for power supply. How can I troubleshoot this
problem.  All my equipments are newly purchased.  

Answer
http://www.caraudiobook.com/car_audio_noise_troubleshooting/car_audio_noise_trou...

http://electronixwarehouse.com/education/accessories/aboutnoise.htm

http://www.mobileaudio.com/rac-faq/rac-faq_2.html

The above sites may give you some places to start.

There are so many causes of electrical noise. It can be improper installation; badly designed products; mismatched wiring; troubles with the electrical system of the car; and new digital data systems that emit impulses that were not anticipated by the aftermarket equipment makers.

In your case since it goes away when the engine is not running, it is safe to assume the ignition system is getting impulse noise into the audio.  You can shut off everything but the power amp and see if it is getting in there; then turn off the preamp, etc.  If you hear is only in one set of speakers it may be the one amplifier that feeds those speakers. If you are hearing it in all the spaekers it is probably getting into the head gear.

Sometimes noise filters must be put on the ignition system of the car; this is something you must take up with the car maker.

So, you must do some testing and see if you can determine the problem a little more precisely.  If it were my system I would take it to a shop that specializes in custom aftermarket installations and have the look at it; they have filters and test gear they use in troubleshooting these kinds of problems.

Good Luck,
Cleggsan