So I just got a 12in. Alpine TypeR sub installed to factory battery w/ monster wires. I have a capacitor and 1200w sub installed.

Problem: The power fluctuates when driving. How I know? The bass starts off loud, then it gets low then loud then low.

Does nebody that knows a lot about stereos may know the problem to this?
Please give me some suggestions! Thanx in advance...

 

What amp is powering your sub? What sized power/ground wire is used for wiring the amplifier? How many amps is your alternator's output? What is your battery's voltage reading when the car is off? On without the stereo playing? With the stereo playing?

 

A capacitor with the stock battery is a complete waste.

 

I have a 1200w 2 channel Audiophonics amp. I dont know the wire gauge exactly but its around 1/2in. thick.

When car is off w/out stereo playing, it reads 12...stereo playing it jumps between 11-12. When car is on w/out stereo playing it reads 12...stereo playing jumps between 13-15, and after driving for bit and stopping, it reads 12.

 

Do you have some type of digital processor to clean up the signal coming from the stock amp? If not then of course you're not going to be getting the proper sound you're looking for. A processor takes the oem signal, cleans it up and delivers a smooth linear high voltage pre amp signal to your aftermarket amps.