What is the cause of engine wine in a mobile audio system. is it basically a ground loop somewhere in the vehicle, or is there other causes. What are all the factors that we know about that can cause this.

Also what are all the different kinds of noises found in the mobile audio enviroment, and the differences. I.E.- Pink noise, white noise, engine noise....

and one last Q.
The little back box found on the constant on alot of decks. what is this box, is it just a noise elimination box, is it nessecary to the radio, could it limit voltage or have any bad effects? And also on some pioneers there is a small back plastic thing on the constant, like a small fuse holder, but without a fuse and a lil bit smaller. What is this. Would you void the warranty to your deck if you were to remove these?

Thanks guys

First, that little box on the constant wire is for RFI suppression. To put it simple, it is a filter designed to limit any noise on the wire coming into the deck. To put is real simple it is a coil(inductor) To put is even simpler--it is some wire wrapped around a piece of metal that the constant wire passes through

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Originally posted by bullseye17:
What is the cause of engine wine in a mobile audio system.

Engine, or Alternator Whine is most commonly caused by use of improper grounding techniques.
For example, using ground points of differing resistances for the various components in your system, head unit, equalizer, electronic crossover, amplifiers.
Ideally each of the components that make up your system should have the same amount of resistance when referenced to the main power source for the vehicle.
This is true even if your system has multiple batteries or capacitors.
Other causes for poor reference ground are listed below:

• Poor ground: failure to clean the area to which you've chosen for your ground(i.e., dirt, paint, primer, body coatings...).
• Poor ground point: use of metal "parts" of the vehicle, it's best to go straight to the frame if you can.
• Lack of ground: failure to ground components that require a ground to keep internal components from becoming radio receivers.

Is it basically a ground loop somewhere in the vehicle, or is there other causes.

Most likely, but there are other causes such as mismatched impedances between components, EMI, RFI, inductive coupling, poor level matching and the occasional loose "nut" behind the crimpers.

What are all the factors that we know about that can cause this.

Noise in audio systems can have a wide variety of origins.

• Alternator: usually a high frequency whine that changes pitch as the RPM's of the engine rise and fall.
• Ignition: a ticking, sound that increases or decreases in frequency as the RPM's of the engine rise and fall.
• Turnsignals / Hazards: a clicking or popping sound synchronized with the flashing of the lights.
• ECM's and BCM's: rarely the actual culprit, but when combined with poor grounding they can cause some noise

Also what are all the different kinds of noises found in the mobile audio enviroment, and the differences. I.E.- Pink noise, white noise, engine noise....

First off, "Pink Noise" isn't just found lying around, neither is "White Noise." These are generated sound patterns that are used to anlize the sound produced by your system. When used in conjunction with a Real Time Analizer (RTA), these allow you to "see" the sound for further analysis.

• Pink noise: A sound which contains all of the frequencies perceptable to the human ear, typically 20 Hz to 20 KHz. Is used during extensive system equalization.
• Ignition Noise
• EMI
• RFI
• RAP

The little back box found on the constant on alot of decks, what is this box?

A noise filter, and in some cases a fuse holder as well.

Is it just a noise elimination box, is it nessecary to the radio, could it limit voltage or have any bad effects?

It doesn't limit voltage to the point that the head unit would suffer any ill effects, so leave it there.

And also on some pioneers there is a small back plastic thing on the constant, like a small fuse holder, but without a fuse and a lil bit smaller, what is this?

That my friend is a pico fuse, I think that's spelled correctly, anyway it's a fuse of sorts. Some amplifier makers used to use them in their amps a while back, but finding replacements proved to be such a nightmare that this practice was discontinued.

Would you void the warranty to your deck if you were to remove these?

Well that depends on the policies of the store where you bought the unit.

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