- 1). Smooth the corners of each piece of plywood with a power sander. This will allow them to fit together more smoothly, and will also allow the carpeting to sit flush over the wood.
- 2). Place your subwoofer on one of the pieces of the plywood. Trace the circular outline of the subwoofer using a pencil. Make sure to press hard when tracing, so that you can easily see the markings.
- 3). Drill a pilot hole about 1/2 inch inside the tracing marks on the board. Use a jig-saw to cut around the outline, staying around 1/2 inch inside the lines. This will create the hole where your subwoofer will reside.
- 4). Cut the carpeting into five 2-by-2 foot sheets using a pair of shears or heavy-duty scissors. Place the board that you just cut a hole in on top of one of the sheets. Use a marker to trace the hole onto the carpeting. Then, again using the shears or scissors, cut around the outline.
- 5). Drill the five pieces of plywood together so that they make a cube with a missing bottom. Make sure to place at least three screws along each edge for adequate support.
- 6). Use carpentry glue to place all the sheets of carpeting over the top of the plywood. Try to line up the piece with the subwoofer hole as perfectly as possible. Allow the glue to dry overnight before continuing.
- 7). Place a screw into each corner of the carpeting using a power drill. Then, place the subwoofer into the hole in the front of the enclosure. Place a screw through each of its bolt holes to secure it.
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