Hey Andrew, your 1st box is holding up great... Just not hitting the lows as hard as I wanted, mainly due to me keeping the box pretty small for a 15... I wanna go BIG this time, with as much volume and port area as possible ! Could you quote me on a new box? - Max dimensions are 34"Width x 18"Height x 20" Depth - I want to get 4 cubes if possible with 16-18 sq.in. of port area, 30hz - Sub/port back, no carpet, double baffle, regular port. Sub Info: Sub OD: 15.625” Cut ID: 14.125” Mounting depth: 8.500” Displacement: 0.19cuft Take your time, and thanks in advance!