How to Build a 4 Speaker Subwoofer Enclosure
- 1). Measure the depth of the subs. If they are are all the same, you only need to measure one. Calculate the minimum depth of the sub enclosure by adding 2 inches to the depth of the subs. Also calculate the minimum size needed around each sub by adding 1 inch to the diameter of the sub.
- 2). Decide the orientation of your four subs. You can arrange all four in a line, although it's likely they won't fit correctly in any of your spaces. You could mount the speakers in the top of the enclosure with all four in a square configuration and facing up, or mount two in the front and two on the top. The only configuration you want to avoid is two in the front and two in the back because the speakers will interfere with each other and hurt the quality of the sound.
- 3). Use the measurements of the speakers to create a rough plan of your box.
- 4). Cut the medium-density fibreboard into pieces for each section of the box. If you are mounting all of the speakers in the same side, you should cut two pieces for that side so you have a double thickness for strength. Draw the outlines for the speakers in the positions you shave chosen from then and draw the outline of the terminal cap in the back panel of the enclosure. The terminal cap is a device with two terminals on the outside and two on the inside. This means the inside of the speaker can be wired permanently but it can still be easily disconnected on the outside.
- 5). Drill a hole in the center of each of the outlines, insert the jigsaw through the hole and cut around the outline to make a hole for each speaker. Do the same for the terminal cap in the rear panel of the speaker.
- 6). Assemble the box. Use the wood glue and screws to hold the sides together and screw the longer sides into the short sides for the most strength. Once the glue has dried, use the silicon caulk to seal the inside of the joints. This seals the box and adds strength.
- 7). Install the terminal cup in the rear panel. Hold it in place and secure it with screws. Attach the speaker wire to the terminal cup on the rear of enclosure, run it through the box and out to the first speaker, and secure it to the terminals on the back of the first speaker. Attach two different wires to the same terminal and run them through the enclosure to the second speaker, and attach them to the terminals on the second speaker. Repeat this process until all of the speakers are wired together.
- 8). Secure all of the speakers in their place with screws. Use the nonhardening rope caulk to seal around the edge of the speakers. This will help prevent buzzing when the speakers are playing. Once you have finished installing the speakers, you can install the box in your vehicle. Connect the wires from the amplifier in the vehicle to the terminal cup.
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