grounding kits are they snake oil???
10-02-2003, 04:38 AM
#1
grounding kits are they snake oil???
maybe someone who is an expert can comment? dont multiple points create ground loops, adding noise to stereo? What of the differences between voltages on ground points. Again i am no expert.
thanks<ul><li><a href="http://g35driver.com/forums/showflat.php?Cat=&Board=FAQ&Number=82596&a mp;page=0&view=collapsed&sb=5&part=">h ttp://g35driver.com/forums/showflat.php?Cat=&Board=FAQ&Number=82596&a mp;page=0&view=collapsed
thanks<ul><li><a href="http://g35driver.com/forums/showflat.php?Cat=&Board=FAQ&Number=82596&a mp;page=0&view=collapsed&sb=5&part=">h ttp://g35driver.com/forums/showflat.php?Cat=&Board=FAQ&Number=82596&a mp;page=0&view=collapsed
10-02-2003, 04:42 AM
#2
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All stereo components should use the same ground point
The "default" one is under the shifter trim area.
I see no reason to bother the engine ground, at least not in the S4, or as long as the engine/battery/alternator path is outside the audio components.
I see no reason to bother the engine ground, at least not in the S4, or as long as the engine/battery/alternator path is outside the audio components.
10-02-2003, 04:53 AM
#3
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I'm not so sure that I'd agree with this.
Common grounding can lead to ground-loop noise. It works in some applications, but I don't think that it should be used as a blanket rule, especially when there are many valid grounding points on a particular car, and components are not necessarily always installed close to one another. The last thing I'd want to do is to run an 8-foot ground cable from my trunk back up to the shifter area, when I can find plenty of grounding points in the rear of the car. I'm a stickler for noise absence, and I've never heard anyone insist on a common ground for all components.
10-02-2003, 05:43 AM
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Depends on the car, I've found.
In my Infiniti years ago, I needed to ground the amp and signal processor (in the trunk) to the same ground point as the radio. I actually wired it the other way -- ran a new ground for the head unit to the trunk.
In my Celica, I didn't need to do any of that, and that was a competition system. The amp's ground point was pretty close to the head unit's, though (less than two feet away).
In my Celica, I didn't need to do any of that, and that was a competition system. The amp's ground point was pretty close to the head unit's, though (less than two feet away).
10-02-2003, 05:50 AM
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A few basics of grounding:
When you're running amplifiers in the car, you want to have ground wires at least the same thickness as that component's power wire. You also want the ground wire run to be as short as possible. Imagine the amplifier only as a tool that alters the flux of electrons through it. To have adequate amplification, you need the flow to be able to transfer in and out evenly, and not "back up" on either side. A backup may result from very long runs of ground wire due to the added resistance from more wire. This is not exactly what's going on, but it's good enough to give you the idea.
On the other hand, when you ground to your car's chassis, it's not a true ground. The metal in the chassis acts as a large "sea of electrons" just like the earth would, but in this case you're only grounding locally. Electromagnetic flux (EMF) can cause voltage potential differentials at varying points in the chassis. This means that your amp is grounding to a different voltage than your car engine (and battery) where the power is coming from. As a result, you can get a touch of noise in the line, which is amplified by your amplifier.
Overall, this effect is not nearly as bad as grounding your amps 10' from where they are located. So the best thing to do is to make sure that your battery is grounded to your engine with a low guage (large) wire. Once again, it should be at least as large as the power wire you're running to your amp. The other thing is to ground amps to a chassis point as close as possible (< 2' is best).
Hope this helps.
On the other hand, when you ground to your car's chassis, it's not a true ground. The metal in the chassis acts as a large "sea of electrons" just like the earth would, but in this case you're only grounding locally. Electromagnetic flux (EMF) can cause voltage potential differentials at varying points in the chassis. This means that your amp is grounding to a different voltage than your car engine (and battery) where the power is coming from. As a result, you can get a touch of noise in the line, which is amplified by your amplifier.
Overall, this effect is not nearly as bad as grounding your amps 10' from where they are located. So the best thing to do is to make sure that your battery is grounded to your engine with a low guage (large) wire. Once again, it should be at least as large as the power wire you're running to your amp. The other thing is to ground amps to a chassis point as close as possible (< 2' is best).
Hope this helps.
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10-02-2003, 06:16 AM
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Common grounding eliminates ground loop noises.
I know of what I speak. If your radio is grounded in the front, and your amp in the back, the shield on your audio lines WILL carry current, and noise. With a single ground, they cannot carry current. Even the Bose amp is grounded up front.
And the distance is more like 4-5 feet, the radio ground meets you 1/3 of the way, beside the shifter.
And the distance is more like 4-5 feet, the radio ground meets you 1/3 of the way, beside the shifter.
10-02-2003, 06:22 AM
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You might get away with "close" grounds, but remember,
whatever voltage differential there is between the two points will be across your audio shield, and amplified.
Now if you run optical digital audio, or balanced line analog, you can ground where ever you want to.
Now if you run optical digital audio, or balanced line analog, you can ground where ever you want to.