Do you guys think it would be worth it to wall 2 xfl 15s? I have 7.5 cubes easy. Im thinking tuning between 33-36hz. I have them in a 7 cube box now with the port 6 inches from the hatch. It did 146 at 33hz with some ***tty ports and a at 1200.1 at a half ohm. Now have 2 1200.1s and a singer 200amp alt on the way. How much louder would a wall get?