Jl audio i have a jl 1000 mono when i turn the bass up the amp cuts off showing low voltage the amp was really hot i have had my stereo all the way up before never had this happen all the wires are good when i look at the cap when the amp cuts off its showing about 8.2 volts

add more batteries to the truck and up grade the alternator and fuse

Do you have a capacitor????? If not, when its up loud and hitting hard it might be going into protection because of a voltage sag....If it goes below 11.8v they will usually do that.....Get a multi meter and put on the hot and ground of your amp when its playing loud and see what the voltage is dropping to.....If its going below 12v, thats your remedy...gd luck....

it depends if the amp is mono or stereo and if it is bridged. if it is bridged the amp cant handle the speaker the best way is to lower the level on the amp or connect it to only one channel. also you might want to check your ground cable use a thick one and make sure its making good contact with the chassis. this happened to me. luck

do you have the amp knobs cranked?? gain and freq

You should definitely upgrade the power wire to the sub amp to 4 gauge -absolutely your choking your amp its starving for current-poor thing is starving !!!!!!!

1. set the amp LP filter frequency at about 80hz and mode/slope to 24db.
2. set the amp gain as recommended in the manual.
3. set the subsonic to on and to about 25hz
4. ste the bass eq to off!
5. set the input voltage to low and signal sensing to off
6. Fine tune by ear.

Are you sure you don't have any shorted wiring or defective speakers?

Quick primer here... Impedance drops with frequency,
you might have the amp loaded at what seems a rated spec.
However if your bassing too hard the voice coil can leave the gap (magnetic Field) and drop your impedance far enough to activate the protect circuit. This usually occurs in a bridged amp.
You can always give JL ( John and Larry actually) a call.They are a outstanding Company to deal with.
Is Maynard still with them ???
Sumthin

Hello highs31 Ok this is a common problem and the fix is quite easy. even though you may not want to hear it. Here it goes: Your amplifier is drawing more current then your alternator can put out and more then your voltage regulator can control. This means that you must and I repeat must add another battery, alternator, and voltage regulator for your sound system. adding these components will eliminate your problems. That is the long and the short of it. I hope this helps, Thank you, Shuttle83

JL amps are somewhat sensitive to low voltage. Everything has to be perfect in the power supply feeding the amp. I'll assume that you have large enough wire. Check the owner's manual on the JL site. They likely recommend 4g or larger. You need to measure the voltage across the B+ and ground terminals of the amp. If it's dropping below ~11v when you turn the volume up, you need to determine why. Make the same measurements at the battery terminals. If there is significantly less voltage drop there when the volume is increased, check all of the points in the circuit where there could be a bad connection. Look for corrosion, over-heated connection on fuses or at the battery and make sure the fuse is in good physical condition. Some types tend to overheat and melt. If everything looks OK, begin measuring the voltage at each point where there is any sort of connector. If for example, you get a significant difference in the voltage on each side of the fuse, the fuse, the holder or the connections to the holder may be defective.