Right now Im running 2 rockford fostgate r1 12s, I was planning on replacing them with 2 SA-12s. My question is would I get more bass out of simply keeping the r1's and just adding 2 10's in a stealth box under the rear seats and a new amp?

 

By the way my two twelves are currently just sitting on top the rear seats of my 2008 supercab. And I have already done the big 3 upgrade

 

Put the 12's under the rear seat in a down firing box. You will have more bass

 

I got a 2.5" LMI seat lift and a custom box for 2 Rockford P3 12's. Already made my back window leak like a mother and makes people nauseous! It's crazy how hard they hit for a sealed box