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Hey guys,
I have two 12" subs that are inverted meaning that the positive and negatives gates are on the outside and easily accessible. I just recently installed lights under my dash by pulling from my cigarette lighter power supply and they work fine. My next addition I would like it to make lights pulse to the beat of my music. I thought I'd ask on here because you guys can help me along the way and not just give me a one time, non-responsive answer.
My understanding: The subwoofers release the bass when the current is run to the amp and then the amp amplifies it to power the subs. So to make the lights pulse to the beat of my music, I could plug the corresponding pos and neg wires the the pos and neg feeds on my subs. I'm thinking that the amps wouldn't match up too nicely so I'm guessing I would need some kind of device like a resistor to compensate the difference. Please pardon me on my ignorance.. and feel free to correct where I am wrong.
Thanks for any response!!
Here is a picture of my lights if anyone cares. I'm still in the phase of being proud of myself haha

Hi Welcome to the forum,
I think all you need is something like this.
http://www.streetglow.com/Music-Interface-ANMI2

Chris has you going in the right direction, so i figured I would explain why.

The light kit you have uses a 12 volt DC supply (standard car voltage)

The output on the amp is variable voltage ac current. I've had amps put out over 50 volts AC at 40 HZ

So basically you have two problems with your original idea. One the voltage types aren't compatible. DC is like a regular 1.5 volt AA battery. You have a set output, as long as its connected. AC is "alternating" current. So its always changing.

Two the output on your subs varies with volume and music. So yes it would be a cool effect if it would work, but the output might be well below, or even excede the capabilities of the lights (if they could work in ac)