Hi guys,

I need some help with my amp creating a lot of noise. I would like to know if anyone else has an amp installed and if they also experience noise coming through? If you don't, how do you have the amp wired up as i have a feeling i need to run a negative cable directly from the amp to the battery.

I'm suffering a bit of noise too, alternater whine i beleive.

I read this (http://www.termpro.com/articles/noise.html), and my amp earth is next.

Can you descride the noise you are getting?
Could be alternator whine or interferance noise
Alternator whine sounds like a supercharger as the noise builds up in revs, normally installing a 0ga ground from negative terminal on battery to chassy will fix problem
The other noise is a constant stadic noise, normally get this when the RCA cables are too close to power wires, try rerouting them down the centre on the car

I just got an amp installed about a week ago - the installers were very attentive about noise. They were going to fit a filter if required but I don't get any engine induced noise, rather I get a slight hiss all the time whether the sound system is on or not. Just like Roberto said about RCA cables etc.

depends on the quality of the amplifier and the cabling...
my amplifier is mounted under the parcel shelf , power wire up the left side of the car from the battery , large earth cable mounted in the back , and all RCA/signal cables up the right side of the car....and there is not a noise.
keep the power and signal wires away from each other and that removes a large portion of the problem...

certainly no need to connect an amp earth directly to a battery..

The Earth wire needs to be as short as humanly possible and of the same Gauge as the power wire connected to an earth that is clean with no paint..

well i never had any alternator noise, and when i changed my head unit i suddenly got alternator noise.
i didnt change any wiring at the amp/speaker end.

What Head unit did you get ?

The Earth wire needs to be as short as humanly possible and of the same Gauge as the power wire connected to an earth that is clean with no paint..
Its better if the ground wire is thicker then the power wire

Earth wire just needs to be adequate. While bigger is better, as magnat said if it is the same size as the power you can't go wrong. Remember that 50-100cm of earth will be able to conduct more current then the same size power cable at 5meters.

Always advisable to upgrade the battery negative terminal to the chassis as well.

You need to do some troubleshooting yourself to find where it is coming from.

Its better if the ground wire is thicker then the power wire

current flowing through your ground wire is same as current flowing through your positive wire (so no diff based on current.) It's true that a thicker wire has less resistance but I wouldn't go as far to say it will make a difference running a thicker ground wire than power wire. Lower level potentials are more prone to interference but you have to remember that the positive cable is MUCH longer. So IMO just keep both cables as short as possible and use the same cable.

Another important one I should add is dont Coil your excess power wire under the boot or under the carpet as this can create and element and cause a fire.. Run the power cable no further then you need it to be , cut off excess and then re-attached your chosen connection.. This is the reason why most power cables come with a fuse holder that has a clamped on or Screwed on connection.. so you can trim the wire to the right length..