07BronzeFuz,
I had a pair of PBX es12d's in a ported box. 3/4" MDF with exterior dimensions of 36"W x 22"D x 14"H which has an internal volume of about 5.2 cubic feet. 2 4"dia x 12" vents. Open interior with blocked inner corners, 2 sections of cross bracing, seams air-nailed and poly-glued...