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Earthing The Head Unit

Edge

By Edge,
in Car Audio & Electrical

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Edge Proficient

Edge

Posted
Posted

Why is it not ok to connect a head unit using a loom converter and just use the factory earth through the loom?

Is it really necessary to earth the head unit directly to the chassis?

Does this remove alternator noise not associated with the RCA's positioning?

Does an apexi super grounding system help to eliminate alternator noise?

A small 10cm long capacitor used inline with the power to my amp reduced the spark plug noise by 1/2 but did not completely eliminate it. Would getting one of those giant 30cm long lightning stick capacitors work for me? My battery is in the engine bay, does adding an extra battery in the boot in the way of the power to the amp help?

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nsanity Rising Star

nsanity

Posted
Posted (edited)
Why is it not ok to connect a head unit using a loom converter and just use the factory earth through the loom?

Is it really necessary to earth the head unit directly to the chassis?

Does this remove alternator noise not associated with the RCA's positioning?

Does an apexi super grounding system help to eliminate alternator noise?

A small 10cm long capacitor used inline with the power to my amp reduced the spark plug noise by 1/2 but did not completely eliminate it. Would getting one of those giant 30cm long lightning stick capacitors work for me? My battery is in the engine bay, does adding an extra battery in the boot in the way of the power to the amp help?

I too am interested in this.

The guy who installed my system is asking for a day to try and get the noise out of it (free of charge - warranty) - and i simply cannot afford a whole day without my car at the moment (bloody work...).

Edited by nsanity
ron Rising Star

ron

Posted
Posted

hi, when you get hums or whine noises that you hear from car audio systems, it is caused by electrical interference. most good head unit should not emits any of this audible noise. by saying that, your car's electrical system can also be the problem, old components may create a fault or picked up some sort of interference and this is put straight back through the car's power lines powering your head unit.

Old and tired batteries can cause this problem also.

a good car audio installer will use your factory wiring looms, why? because these cables are dedicated for your sound system and hence your head unit is not crossed wired to anything eles. also solder all contacts and heatshrink/taped all bare wires as it can easily pick up interference from current running through other wires.

noise suppressor can sometimes help and you can get them from Jaycar

Primordial Grand Master

Primordial

Posted
Posted

i dont know if someone has mentioned it, but making sure your RCA's are running NOWHERE NEAR your power wires for amps and alike is vital. The best way is to run them down opposite sides of the car. Good quality RCA cables reduce alternator whine too as they're generally better shielded.

Chris Rogers Grand Master

Chris Rogers

Posted
Posted
i dont know if someone has mentioned it, but making sure your RCA's are running NOWHERE NEAR your power wires for amps and alike is vital. The best way is to run them down opposite sides of the car. Good quality RCA cables reduce alternator whine too as they're generally better shielded.

actually if you use twisted pair leads it does help for noise rejection. the car is a noisey car unfortunately and what may work for one may not work on another.

AdamsR33 Mentor

AdamsR33

Posted
Posted

I had this noise too, found that my RCA wires from the H/U to my amp in the boot was running too close to the earth wire coming from the battery to ground!!! just rerouted them away from the ground wire and noise gone.

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