Help with Car Audio Amplifier and Subwoofer

Thread Starter


Joined Dec 18, 2011
I have been running into my amps getting the protection lights going off erratically

I have tried nearly every combination under the sun to try and diagnose this problem with no avail.

Currently I have 2 amps (not both installed simultaneously) I know both work, because I have gotten spurts of how they SHOULD sound at times.

I am running a single 12" 4ohm DVC sub.
Both amps technically go to 2ohm stable from one channel, and when bridged they are 4 ohm stable.

I have also tested the ground, Battery+, and remote with a multimeter, and gotten 12+V everytime.

The sub has produced sound how its supposed to for a short duration before the amp goes into protection mode.

I have tried wiring the system so that i get a mono bridged output from the amp, and wired the sub in series (8ohm) and the light will not come on, but no sound comes out.

I have wired the sub properly (2 4Ohm outputs), and occasionally proper output will occur but for no longer than 5 seconds before the protection light comes on.

I have also tried wiring the sub in parallel (2ohms) and just running it from one channel, (amp is supposedly 2ohm stable) it produces sounds and moderate movement, but the amp terminals start smoking (melting plastic). BUT no protection light, no matter how long the duration.

Both amps react the exact same way, so that leads me to believe there's nothing wrong with the amps, but i don't know...

HALP. How can i test the sub or the HU to identify the problem?


Joined Feb 19, 2009
What gauge is your supply wire?

What do you read for voltage when you turn the amp on (load the wire), before protection kicks in?

Bridging to 2Ω, or any other configuration that generates that amount of heat means your speaker wire is too small, your power wire is too small, or you may be blowing up your amp. Some amps are more stable than others.

What brand and model number are your amplifiers?

Do you have an active low pass filter in front of the amp, or the low pass setting on the amp turned on?

What brand/model number are the speaker(s)?

Thread Starter


Joined Dec 18, 2011
here's the amp i am mainly using
here's the sub{keyword}&gclid=COvF2tKWja0CFWcBQAodaTNAoQ
the other amp is a polk audio pa660

the wire gauge thing makes sense for the 2ohm wiring since i was using small gauge wiring and sending both voice coils mainly through one wire even though it was only pumping out max 150w rms through a 16g wire.
the only low pass filter i have is on the amp, like i mentioned it has produced what it should for spurts of time. I am using a 4g supply wire. and i was reading 12.# V


Joined Mar 14, 2008
Have you measured the impedance of you speaker? Sounds like you have a short somewhere in the speaker circuit. Do you have a different speaker you can try?