So I thought I would try a 4th order bandpass build. I am using the same sub I had before in a 3.5 cubes ported enclosure tuned at 34hz. Single C2 Audio Threatcon-2 15 dual 4ohm VC.
So I built this one. Specs are 2 cubes sealed, 3.5 ported at 45-46hz with a 50" of port area.
Forgot to get a picture after I rounded off all the edges.