I recently purchased two 10 inch kicker subs and an alpine amp, and I am having a problem with the bass from the aftermarket sub. The sub is not giving off enough bass that i want from it, i was wondering if its a conflict with the factory amp. My brother has the same after market subs and amp in his Acura integra it is works perfectly fine and produces lots of bass. This is why iam assuming its a problem with the factory amp in my cobalt.

 

Aftermarket or stock deck? the stock amp shouldn't interfere, especially if you have an aftermarket deck.

 

I have a alpine CDA-105 deck.

 

unplug one of the speakers and see if it gets louder or quieter

 

And it's safe to assume the SUB mode is on? Or maybe the pre-outs are set as rear instead of sub? My ex's car had that option on the deck iirc