Ground wire question
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Instructor
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From: Almost Canada
Ground wire question
I'm kind of a newbie on car stereo stuff, I was wondering why I just can't run a thick ground wire right from the battery post and pick up ground on the head and equalizers from that wire, and then run it all the way to the amps in the trunk? Why do I have to pick up ground from the frame in the trunk?
Last edited by WoodyJohnson; Aug 15, 2017 at 09:24 AM.
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From: Bradenton, FL
I'm kind of a newbie on car stereo stuff, I was wondering why I just can't run a thick ground wire right from the battery post and pick up ground on the head and equalizers from that wire, and then run it all the way to the amps in the trunk? Why do I have to pick up ground from the frame in the trunk?
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From: Almost Canada
Well, theoretically you could reduce your wire size at each junction, couldn't you?
Melting Slicks
Joined: Oct 2004
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From: Woodland CA
It does not make sense to run a new ground wire from the battery to the head unit, it already has a ground. And you should not pick up the ground from the head unit and lead it to your amp, that wire is not good enough for that type of power.
You can run a 4 AWG wire from the battery to the amp or if multiple amps, to a ground distribution block. From that block, you can hook up the ground for all your amps.
One of the reason people don't ground at the battery is because of the old rule of keeping the ground wire as short as possible. From the battery to the amp that wire could end up being a 10-12 foot long while grounding to a near by bolt (or drilling your own) could be as short as 2-3 feet. I honestly don't know if the length of the ground wire makes a difference. Maybe there is a greater chance of a ground loop (whine sound) the longer the wire is, but that's just a guess because there are many factors that can cause a ground loop.
You can run a 4 AWG wire from the battery to the amp or if multiple amps, to a ground distribution block. From that block, you can hook up the ground for all your amps.
One of the reason people don't ground at the battery is because of the old rule of keeping the ground wire as short as possible. From the battery to the amp that wire could end up being a 10-12 foot long while grounding to a near by bolt (or drilling your own) could be as short as 2-3 feet. I honestly don't know if the length of the ground wire makes a difference. Maybe there is a greater chance of a ground loop (whine sound) the longer the wire is, but that's just a guess because there are many factors that can cause a ground loop.
Last edited by Homer3D; Aug 15, 2017 at 04:22 PM.
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From: Troy & Dearborn, Michigan
^^^
Sorta true on length of grounding wire. The real reason is why use a wire (which has a high level of resistance) when you can use a grounding plane (which doesn't).
The also keeps your grounds "cleaner" as they are all common and the resistance is similar. Most high amp systems use the frame, body, or chassis ground plane (different cars use different grounding schemes).
Sorta true on length of grounding wire. The real reason is why use a wire (which has a high level of resistance) when you can use a grounding plane (which doesn't).
The also keeps your grounds "cleaner" as they are all common and the resistance is similar. Most high amp systems use the frame, body, or chassis ground plane (different cars use different grounding schemes).
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From: Bradenton, FL
Why the aversion to using a local grounding point?
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From: Almost Canada
I dunno, it just seems to me it would eliminate the potential for multiple return paths for the audio grounding system, since there is not a second path through the ground conductor, eliminating the possibility of a ground loop that would pick up mechanical noise. Are the front and rear chassis systems grounded together on a C5 vette?
Last edited by WoodyJohnson; Aug 17, 2017 at 02:03 PM.
