Ground short or long? Does it matter?

[jeepster 10+ year member]

I can't really find a place I'm confortable drilling into for a ground, would it be wise to run the ground all the way from the battery along with the power? I know the battery would be the best place to ground the amp in the first place as its of the lowest resistance, but I wasn't too sure how the long run would affect it.

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[brtnboarder3241 5,000+ posts]

battery for ground is fine

 

[bk all day 10+ year member]

i am no pro but i am sure the ground should be as short as possible.

 

[sonic purity 10+ year member]

Yes, you want the ground wire to be as short as it can, and directly to the body. You also want to make sure you have a ground going from the battery to the body.

 

[sonic purity 10+ year member]

If your worried about drilling into the car, then use the seat belt bolts. Just grind some of the paint off so you have a good connection to ground.

 

[.::DuD3::. 10+ year member]

I don't see why it would be a bad idea to run all the way to the battery.

 

[sonic purity 10+ year member]

You can run the ground all the way back to the battery and be fine, the reason its better to be shorter is that its less resistance for the power and the longer you ground wire the more chance of inducing noise into the system.

 

[helotaxi 5,000+ posts]

Running the power and the ground side by side from the battery is perfectly OK. No chance for noise from that. Can't say the same using a chassis ground. Grounding to the battery give you a known good ground every time. The resistance of a run of copper wire of sufficient gauge to handle the current draw of the amp is going to have negligible resistance. So low in fact that a normal DMM won't be able to measure it.

 

[BEAVER.989 10+ year member]

I was taught to ground to the chassis. The explanation was that this allows the current to travel through the entire car body rather than a small wire.

While this is a good theory and may have some merit, I've come to realize that the battery is an acceptable ground, as well.

 

[helotaxi 5,000+ posts]

The thing about "allows current to travel through the entire car body" is that current takes the path of least resistance. Imagine the car as hundreds of individual current pathways of different resistance (all of them much greater than a properly sized run of copper wire) wired in parallel. The resultant resistance migh be lower than that of the wire or it might not. You really have no way of knowing. You also don't know what factory installed components of the car (brake lights, fuel pump, etc...) are sharing which of those pathways with you amps' ground. Shared pathways CAN lead to noise such as a click when you apply the brakes or a ticking in the system when you turn on the turn signal. If you use the same size wire for the powr and hte ground and it is properly sized for the current requirements of hte amp and the length of the run, both will be more than adequate to carry the current with negligible voltage drop and zero chance for noise. That's all you care about.

 

[hoxie08 5,000+ posts]

yeah just make sure you use decent size wire and you will not have any problem running a ground to the battery. dont listen to anyone telling you otherwise. shit, make a thread on it if you want and see how many people on here do it with no problems...

 

[Proximity 10+ year member]

Running it straight to the battery is the BEST way to do it. The reason people use the chassis for the ground is that it's much more convenient.