Question about Jl Audio 300/4 Car Audio Amplifier

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Wrong connection continuation

FIRST QUESTION: I bought a stinger 1 farad capacitor, unfortunately i installed it wrong. The positive of the capacitor to the ground and the negative of capacitor to the B+ of the baterry. My 300/4 JL amp don't work also with my sufwoofer amp. What should I do. I may have damaged the capacitor for my subwoofer amp as well.
REPLY: You should have blown a fuse. Check the main power fuse feeding the system (usually at the battery). If it appears to be good, you'll need a multimeter to check the voltage at the B+ and remote terminals of the amplifiers. Place the black meter lead on the ground terminal of the amp when testing. .
SECOND QUESTION: When I turned ON my system my amps stays off (doesn't power on). Meter reading from ground to remote is 24.5v while terminal to ground is 2.4v. When its OFF, my terminal reads 24.5v and remote 0v. What should i do to fix the problem?

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Re: wrong connection continuation

If you're installing this in a vehicle with a 12 volt charging system (most automobiles are 12v), I think the batteries may be dead in your multimeter. You shouldn't read anything over ~15v.

When you measure this again, place the black lead on the ground terminal of the amp.

Posted on Dec 17, 2007

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. Kind of like when someone squeezes a garden hose2_bing.gif when your trying to use it. That would be the high volume, starving the amplifier. The capacitor stores power in it to power the amp at high volume. 2 farads would probably be bulletproof on a single amplifier system, but 1 farad should work well enough. Or seek help from an expert on exactly what size capacitor you should use. If you find yourself saying: My amp cuts out.

If this assisted in solving your problem, please take the time to rate it. Thank you.

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The capacitor should be put in parallel with the main +B voltage of the amplifier. That means you would connect the positive side of the capacitor to the +B voltage supply of the amplifier and the negative side of the capacitor would go to the chassis ground.

If you have it connected in series, or inline with the +B voltage supply, the capacitor would be blocking the voltage to the amplifier.

Without more information on your problem that is the best answer I can give you.
If this does not help, please supply more information and I will be happy to help you further.

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You should have blown a fuse. Check the main power fuse feeding the system (usually at the battery). If it appears to be good, you'll need a multimeter to check the voltage at the B+ and remote terminals of the amplifiers. Place the black meter lead on the ground terminal of the amp when testing. .

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The biggest thing is you have grown more accustomed to the strong bass. And your driving it harder. The battery and length/size of the + and - power cable cannot fully fill this order.  This is why the capacitor are hitting the market.  Get you a 1 Farad capacitor and install it to see the diff.

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