How to Build a Simple Sub Box

Step 5: Finding Center

On my top piece, I marker corner to corner so I can find my center. Depending on the size of your subwoofer, you need to make a circle big enough to fit your speaker and to allow the "lip"  hang over so it can be screwed in.

I needed an 11 1/4" diameter circle. So I also made cross marks between my "X" and measured half that from the center point.  I marked those measurements on my cross lines. (sorry, no picture)

Placing a nail in the center point, tying a string around the nail and to a pencil, I used those marked cross points to guide me as I created a perfect circle. (sorry, no picture)

*If you can find a template, this process will be much faster!*