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Static electricity

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=47684
Printed Date: January 24, 2022 at 10:35 AM


Topic: Static electricity

Posted By: John Luttrell
Subject: Static electricity
Date Posted: January 14, 2005 at 7:35 AM

  Ok guys, first of all I'm an aircraft/auto mechanic by trade with only basic knowledge of audio systems.  I have installed a very basic system in my tacoma 4wd and it sounds great, but when it's cold and dry outside I get popping noise through my speakers when I get out of the truck.  I know it is the static build up that used to shock me when I got out of the truck.  Now it doesn't shock me any more but instead the shock seems to go through my amp.  I have the amp grounded to the cab and 12 volts from the battery to the amp.  I'm wondering if maybe it's because the amp is not mounted but setting on the carpet under my seat.  Does the amp case need a seperate ground if not mounted? Any tips would be appreciated, thx.............



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John Luttrell



Replies:

Posted By: Jay T
Date Posted: January 14, 2005 at 7:47 AM
Double check your grounds on the amp for good clean connection. And make sure your battery posts are clean. Some vehicles are worse than others for build up while driving. Consider using a grounding strip on the bottom of the vehicle to dissipate static while driving.




Posted By: John Luttrell
Date Posted: January 14, 2005 at 7:57 AM
  Thanks Jay, I'll look into that.  I forgot to mention the static build up seems to be in the seat foam which buids up static charge as I slide out of the seat.  Forgot to mention the truck is a lifted 4wd and I can't step out onto the ground so I have to kind of slid out and hop down to the ground.

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John Luttrell




Posted By: Jay T
Date Posted: January 14, 2005 at 8:19 AM

When you "slide" out of the truck and grab the metal on the door to close it, you're grounding any static build up that occured while driving. Grab the metal on your door or frame before you hit the ground, see if that helps





Posted By: John Luttrell
Date Posted: January 14, 2005 at 8:36 AM
  I do that Jay, especially for the fact I used to be the ground for the static before I installed this amp; I think I'm part horse and hate to get shocked.  This is the second amp I have had in the truck, the first one couldn't handle the bad roads I drive on and kept breaking solder internally; but didn't have this static problem.  I got tired of resoldering it so installed this one.  Only difference in install is this one sits on the carpet under the seat, unmounted to add protection from the bad roads and the first amp was mounted to the rear of the cab which also provided a ground for the case.  Thats why I'm starting to think I may need to ground the amp case itself.  I do appriciate the help Jay.......

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John Luttrell




Posted By: Jay T
Date Posted: January 14, 2005 at 10:15 AM

Ya, try to Solder a decent size wire from the amp chassis right to a bare metal spot on the floor under your seat. Just cut I Little hole to fit the wire through.  I don't think this will stop your truck from shocking you but it might stop it from going back through your system to your speakers. 

And once again, just double check the wiring you already have installed. Is you ground wire for your amp as big or bigger than the power wire you have on it?

Let me know how it turns out.





Posted By: John Luttrell
Date Posted: January 14, 2005 at 1:16 PM
  OK Jay, I checked all my connections and they were good.  My power wire and gound wire are the same size, so I installed another large ground wire from the case of the amp to the same ground for the amp on the cab; lol.......and it still does it.  Really has me stumped, so I can definantly use some more ideas.  I know the static is from the seats; I can put my arm next to the seat and the hair on my arm will rise..................lol, know of any way to ground foam in the seats.  Hate to think I will have to replace the seats to get rid of all this static electricity.

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John Luttrell




Posted By: hurtado_roberto
Date Posted: January 14, 2005 at 4:26 PM

How does the static electricity travel to the amp?  How does a grounding strip dissapate the buil-up?  Maybe the popping is associated with some other problem in the installation or a cheap amplifier.  I really don't think the roads you drive on can be as bad as some of the music the competition amplifiers go through.  What amplier brand and model is it?

How can the static electricity go to the amp?  Electricity always takes the path of least resistance right, so should you be grounding the foam or seat somehow.  To find out what wires go to which speaker some people connect a battery to the positive and negative wires and the speaker makes a poping noise.  Maybe the static electricity is going directly to the speakers.  In this case the speaker wires might have been undesireably grounded somewere.



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Poly Dollies




Posted By: Jay T
Date Posted: January 14, 2005 at 4:37 PM

He said this was happening before with another amp but the truck shocked him. I suggest getting a grounding strap for the actual bottom of the vehicle. Lots of people do this. that way when you step out, there is no difference in charge between the earth and the vehicle.

You don't need to ground the seats they are bolted to the frame of the vehicle. But yes maybe do as Hurtado said and double check your speaker leads to make sure nothing is shorting or touching metal.  If any are leads / wires are touching metal, it will pop or make an audiable noise when the static gets dishcarged.





Posted By: John Luttrell
Date Posted: January 14, 2005 at 6:11 PM
    Thanks guys, I'll check the speaker wires for any shorts.  But if a speaker wire was shorted wouldn't that speaker drop off and not work?  They both work fine; I have already checked the drivers side wires so I guess I'll check the passinger side tomorrow,  Thx again guys.

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John Luttrell




Posted By: azidrane
Date Posted: January 14, 2005 at 7:17 PM

#1. Dont ground the chassis of the amp, that will cause a path for a possible ground loop

#2. Check the length of your ground wire. I have seen this static sort of pop from a the amped speakers when the ground is either to long or inadiquate. Try for less then 2".

#3. Check the voltage drop between your Negitive battery terminal and the ground point. It should be no higher then 1v.

What is the amp? What type of power are we dealing with here?





Posted By: John Luttrell
Date Posted: January 14, 2005 at 9:36 PM
    I'll check the voltage drop and shorten the ground wire in the morning; the ground is about 16" long.  The amp is a basic sony 1200 watt amp.  Thx for the pointers..............

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John Luttrell




Posted By: Master Asylum
Date Posted: January 14, 2005 at 9:56 PM

Not sure why some other guys haven't replied here but I coulda sworn there was a topic in this or general discussion within the past month concerning popping. Might be worth searching the forum.

On a side note, I don't know if Jay is entirely getting what John is saying... Could be mistaken, just seems to be some miscommunication.



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1998 Monte Carlo w/
Eclipse CD8454
2xRockford 5.25" Power 2-way T152C
2xRockford 6"x9" Punch 3-way FRC4369
1xMemphis 16-MCH1300 5-channel
2xKicker 12" L5 Solobaric-2 Ohm





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