amp grounding

I have a 92 bmw 535 and was wondering where the best place is to ground the amp??? I am getting engine noise. I have tried about 5 different places and still the same. can I hook up the ground to the batt. and will that get rid of my engine noise, since the batt is under the rear seats?

If I might interject, I've heard about ground cable length before, the same thing about not being longer than 18".  Why is that?

The longer the ground the more resistance.

the reason is that you dont want to add resistance to the wire by having it too long if it was to have resistance the amp would lose voltage or create noise or both.When adding an amp you want them to have the same ground potential as the battery and the factory location of a batteries ground is usually about 12 inches or so so any loner may cause problems. 18 inches is pretty much just an estimate of how long it should be after all 18 inches is almost always plenty to ground.Basically when hooking up anything in a car you dont want added resistance especially in amplifiers.

I am running a jvc 4 channel amp for my mids and a alpine v-12 for my subs. I have a 1 farad stinger cap.  I am running 0 guage pos power wire and about a 10 guage ground wire that is about 2-3 feet long, there isn't much to get a groung from or can I use a self tapping sheet metal screw????

Use a self tapping screw and make sure the chasis metal is bare (no paint, corrosion, carpet, etc).

0 gauge seems a little excessive. But your ground should always be the same gauge as your power (if not larger). So if you're running 0 + then you should be running 0 -. You can use a distribution block to combine your grounds into one, just like your power wires but reversed.

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Squirrel
"No more Cpt. Kirk chit chat"
If its too loud, then you're too old
Donate to the12volt.com

I tried to hook up my amp today its sum oldschool AMA amp 600watt one. just a no brander till i get a good deal on a good one. but i hooked all the wires up (not to the amp yet just to the car). the positive power to the bolt on the positive terminal on the battery. (Not the battery post but the screw that holds the positive clamp on the battery, duno if this is correct.) then i grounded the negative wire to a piece of frame that connected onto the chassi of the car so i didnt have to drill. then i went to hook up the power to the amp and it sparked and then started to smoke. anyone help me. i got no idea aiy. i bought the amp kit from a shop. the power cables are both 6 gauge cable and there is a fuse n everything so i really havent got a clu as to y it would do this.

Did you hook the ground to the amp before you hooked up the positive? If you did, then that was more than likely your mistake. By hooking up a ground before the positive you are allowing the circuit to be completed as soon as the positive comes close enough to arc to the connection point. The arc causes smoking, poping, etc because it is not a "constant" connection yet. Always hook up the positive first, then the ground!

Another way to be safe is to remove the inline fuse at the battery while hooking up the amp. With that fuse removed, you will not have a "hot" wire being hooked to the amp, so you don't run the risk of any arc. Once the positive is hooked up, then the fuse can be reinstalled into the holder/cradle near the battery.

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Squirrel
"No more Cpt. Kirk chit chat"
If its too loud, then you're too old
Donate to the12volt.com

I tried to hooking up the positive first and then the ground wire but it still arked up pretty bad. but there was no smoke this time which is a plus. i didnt remove the inlive fuse. (the amp is pretty old and dodgy i dont really care if it gets f**ked cause i am getting another one soon) but it shouldent ark should it.

if you are using a 0 guage possitive why are you using a ten guage ground.   your killing the fact that you spent the time to run 0 guage wire.. i mean its ok to use 10 guage wire. but use 0 or four gauge into a distribution block and have either 4, 8 guage wire out to the amps. and well jensen ????? could be your problem.

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Jon
Installer/Help Technician
---coral springs florida---
mecp certification is not always needed. I have it and it has not helped me out at all. my experience out shines it.

figured out the problem to my situation. it was the amp I had 2 amps a little good one and a big old sh*tty one and i didnt wanna fuk up the good one so the first time i hooked it up i hooked it up ground first then i hooked it up positive and it sparked so i just assumed that it was my wiring not the amp. thatnx for assistance
AsH