While Kicker says that the L7 will work well in all types of enclosures, a ported box is recommended when the maximum amount of bass is required. While the L7 is available in 8-inch, 10-inch, 12-inch, and 15-inch sizes, the 12-inch version is the most popular and will be the focus of this article. For maximum bass output, the manufacturer recommends a ported box with an internal volume of 3 1/4 cubic feet, and a rectangular port measuring 3 inches x 13 1/4 inches with a length of 14 1/2 inches. This should give the box a tuning frequency of 40hz.
Measure the vehicle that the box will be going into. The exact dimensions and shape of the box are unimportant so long as the internal volume of the box is 3 1/4 cubic feet and the port volume is the same size and shape as the one the manufacturer recommends. Measure the space that the box will be occupying once it is in the car, and the size of the opening of the vehicle that the box will pass through during installation.
Once the dimensions of the box are known, cut the MDF to the size needed. Before assembly, place the pieces in the vehicle to make sure that the box will fit.
Place a bead of wood glue on the surfaces of wood that will be touching. Use wood screws to attach the pieces. Drill a pilot hole before screwing to keep the wood from splitting.
Cut a hole to mount the speaker, and another to add the port. Once all holes are cut, seal the seams inside the box with silicone to prevent air leaks.
Mount the speaker and port to the box using wood screws and a cordless drill. Be careful not to let the drill slip when mounting the speaker as damage to the speaker will occur. Place the box in the vehicle and connect it to the amplifier. Listen and adjust the amplifier according to your taste.
