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2008 chevy trailblazer_ls
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Alright so I was just wondering.. where did you guys bolt your ground at? Pics would be nice.. I think I have a bad ground cus I get really really bad voltage drops for just a 1000 Watt RMS amp.. I mean I know our alts are pretty weak but the voltage drops I get is ridiculous and my amp went into low voltage protection twice yesterday so I don't wanna fry it.. I'll be doing the BIG 3 this weekend I think..
Thanks
 

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2003 chevy trailblazer_ls
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I ran my ground up to the front battery under the hood. Best ground in my opinion.
In most instances, this is a bad idea. All you're doing is adding more wire to get frayed and fail... You're also increasing the length and thus the impediance (more heat, more load, less efficient).

Sometimes you have to do the above, but it's more the exception to the rule, and I'd recommend you try the traditional method of a closer ground.


Personally, I used a bolt under the rear passenger seat -- but one that was directly connected to the body. I do not recommend using anything that goes through a hinge. Connect directly to the body.
 

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2002 gmc envoy_sle
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In most instances, this is a bad idea. All you're doing is adding more wire to get frayed and fail...
Yes you are correct that you have more wire to get frayed and fail, but if routed properly what is it going to rub against and fail?:confused:

You're also increasing the length and thus the impediance (more heat, more load, less efficient).
This is false. Yes you are increasing your length but if you are using the same size ground as you are power wire, then you will minimize your resistance. What has a greater resistence: Copper or sheetmetal/steel with multiple welds?

Copper will have the least resistance and you are trying to return your current back to the neutral terminal of the battery. So if you are capable of running a ground all the way back to the battery in an all copper cable with minimal resistance. Why would you want to run a shorter ground to a bolt in the back of the car that passes the current to sheetmetal, which then passes the current to the steel frame of the truck, then back through another steel ring terminal which is connected to a copper cable back to the battery.

Now you tell me which is the least resistant.

Sometimes you have to do the above, but it's more the exception to the rule, and I'd recommend you try the traditional method of a closer ground.


Personally, I used a bolt under the rear passenger seat -- but one that was directly connected to the body. I do not recommend using anything that goes through a hinge. Connect directly to the body.

Yes you are correct running a cable back to the battery is an exception because when someone is only running a 600W amp the frame in the rear of the car has enough conductivity to carry the required current. Plus most installers are to lazy and/or cheap to run the ground all the way back to the battery.
 

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Yes you are correct that you have more wire to get frayed and fail, but if routed properly what is it going to rub against and fail?:confused:
**** happens. Whenever possible, simplify. The simplest solutions is generally the best, as well.

This is false. Yes you are increasing your length but if you are using the same size ground as you are power wire, then you will minimize your resistance. What has a greater resistence: Copper or sheetmetal/steel with multiple welds?
The battery has a "negative" lug but that is NOT a ground plane. That being said, I do not think you won't be minimizing resistance. I'll grab my ohm meter tonight, and check a few spots to see.

Copper will have the least resistance and you are trying to return your current back to the neutral terminal of the battery. So if you are capable of running a ground all the way back to the battery in an all copper cable with minimal resistance. Why would you want to run a shorter ground to a bolt in the back of the car that passes the current to sheetmetal, which then passes the current to the steel frame of the truck, then back through another steel ring terminal which is connected to a copper cable back to the battery.
return to neutral? You mean negative? You do realize that current "flows" FROM negative TO positive, right? (and yes I know it doesn't really "flow").

Now you tell me which is the least resistant.
I'll check with my ohm meter, later. But as I said, the negative terminal is still not a ground plane... There is additional points of failure with this method... And extra cable length does equal more resistance, more load, and more heat.

Check out forums with real audio pros, and running ground to the chassis is the standard thing to do -- and running to the batt is a special exception, only done when neccessary.

Yes you are correct running a cable back to the battery is an exception because when someone is only running a 600W amp the frame in the rear of the car has enough conductivity to carry the required current. Plus most installers are to lazy and/or cheap to run the ground all the way back to the battery.
The big boys don't run it to the front battery, either. So if the shops don't do it... and the big players don't do it... why the heck are you?
 

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2006 chevy trailblazer_ls
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alright so lets say you have a setup like may with the extra bats in the back and all that, do you run the neg. to the chassis or do you run it back to the neg. on the batt?:undecided
 

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I'll save you the trouble of using an ohm meter. Check out the following link. This is just one example on the net showing the resistivity of different metals. Steel is 10 - 100 times more resistive than copper.

http://resources.schoolscience.co.uk/CDA/16plus/copelech2pg1.html
I will still measure it. I like doing "labs" and other practices that demonstrate "theory".

My concern is does resistance change with mass (and I think it does) so there is a heck of a lot of steel in a car body.....

Furthermore, electricty takes the path of least resistance. With a traditional wire, that path is decided by the installer. And it may run past points that introduce interference and cause problems with audio systems. As where a grounding plane does a very good job at preventing that, in most instances.

And I know that low-volt DC tech can be considerably different than high-volt AC tech, but consider that the Earth itself is a poor conductor, yet we use it as a very effective ground plane -- instead of running a negative wire back to the "pole". Food for thought.

That being said, I will check the resistance of my TB's chassis, and perhaps I will learn something new. But the standard convention remains: ground to the chassis.
 

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2005 chevy trailblazer_ls
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Think of your power and ground cables as freeways. The smaller the cable, the less lanes of traffic you can have.

When you run a ground cable back to the battery, you are limiting the amount of paths the electrons can take back to the source. When you run your ground to the frame, it's like opening up the carpool lanes and letting traffic flow more freely.

Another important note, you need to make sure to have clean connections at your cable ends and where your cables attach to the frame from your amp and from your battery. Clean battery posts are also important. If these areas are not clean you can cause "back ups" and in turn power loss and resistance and heat gains.
 

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I bolted my ground underneath the rear carpet, bolting it under one of the tie downs, using the same bolt. Seems to have worked out so far.
I tried this when installing my amp and it was a bad ground. There is a ground under the drivers side rear door sill panel, Already a screw there too. that's what I'm using as my ground now. I've had no problems with it.
 

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I tried this when installing my amp and it was a bad ground. There is a ground under the drivers side rear door sill panel, Already a screw there too. that's what I'm using as my ground now. I've had no problems with it.
I will have to check for that, I want to change my ground because it isn't attached directly to the frame.
 
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