- 1). Cut six panels for the subwoofer from the sheet of MDF. Two panels should be 12 inches by 12 inches; two panels should be 10 inches by 12 inches; and two panels should be 10 inches by 11 inches.
- 2). Sand the edges of each of the panels to remove splinters or rough edges.
- 3). Assemble the 10-by-12 panels and the 10-by-11 panels into a hollow square, open on parallel sides. The ends of the 10-by-12 panels should overlap the edges of the 10-by-11 panels. Secure the panels together with wood glue and wood screws where they join.
- 4). Attach a length of speaker wire onto the terminals on the back of the subwoofer.
- 5). Cut an opening in the center of one of the 12-by-12 panels for the subwoofer. Mount the subwoofer to the panel with screws in the subwoofer's metal flange.
- 6). Place the panel with the subwoofer onto the box and secure the panel with wood glue and wood screws.
- 7). Drill a hole in the center of the remaining 12-by-12 panel. Feed the end of the speaker wire through the opening, then attach the panel to the box with wood glue and wood screws.
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