How To Make A Ported Subwoofer Box
Learning how to make a ported subwoofer box is easier then it may seem. Although ported subwoofers look amazing when they are done, the materials are inexpensive and easy to assemble.
To make a ported subwoofer box, you will need:
- A circular saw for cutting the wood to specific dimensions(although some home centers will do this for you at no charge, whichever is easier).
- MDF(Medium density fiberboard) or plywood either pre-cut at the store or cut at home.
- A jig saw or router for cutting the speaker holes.
- A hole saw for the ports( a jig saw will work for this also).
- A drill for screwing, pre-drilling and ported holes.
- One and a half inch ABS drain pipe
- Carpet for covering the subwoofer box
The size of the speakers determines the size of the box. We are going to use two twelve inch subwoofers as a basic idea and then if the size is different, the ported subwoofer box can be adjusted. The box will have six holes, two for the subwoofers and four for the ports.
- The face of the ported subwoofer box is the first part to design and build. If the speakers are fourteen inches total (with the rim), then the face of the box needs to be sixteen inches high. The speakers should be three inches apart and six inches from the ends of the box. This makes the face forty three by sixteen inches.
- The next step is to determine the depth of the box. A ported subwoofer box does not sit facing directly forward, it always has a slight tilt so the speakers are angled up. Measure the face of the speaker to the end of the magnet and add two inches for extra room. Lets say this is six inches. The addition two inches makes an eight inch depth. So, the sides need to be sixteen by eight inches. Now don't forget about the angle. A twenty degree angle will give a nice tilt to the speakers. A test board can be used to see which angle works the best. Next cut the top and bottom boards. The sizes should be based on the measurements from the face and side boards.
- Once the top and bottom are cut, then it's time to cut the back piece. This is always last because the size depends on the measurements from the side boards.
- Now that all the pieces are cut for the subwoofer box, its time to cut the speaker and port holes. Measure from the center of the face one and a half inches to each side and make a mark. This should be directly in the center of the face, don't make the mark on the edges. Now hold the speaker upside down on the face and place it against the mark. Rotate the speaker until it is one inch from the top and the bottom. This way if the board was not cut to the exact dimensions the speaker will still fit evenly. Do the same for the other side. After the speaker holes are cut then it's time to use the hole saw for the ports. measure three inches from the center edge of each speaker and make a mark. Now draw a line square with the edge of the subwoofer box. Measure two inches from the top and bottom and make the mark for the hole. Use the hole saw or jig saw to cut the circle for the subwoofer ports.
- It's time for assembly and final touches. Make sure there is some Elmer's glue handy for extra support on joints. Put the sides on first, then the top and bottom, finally finishing with the back. Measure to the back of the subwoofer box through the port holes. Subtract one inch and cut the ABS tubing to fit. This gives a little room for the air to move in and out, but not so much that the speakers just reverberate. Glue the ABS tubing in place with an epoxy or other construction adhesive around the port hole edges.
- Finish the box with carpet for paint. Carpet works well because it helps dampen the vibration and allows for a clearer sound.