Common speaker sizes are 10, 12, 15, and 18 inches. Measure the space to fit the box to make sure you don't buy a speaker that's too big. Plan to build the box around the speaker you buy and the ...

The Bbox 12-inch subwoofer box is a twin-vented enclosure with an 11.12-inch hole cutout. While it might look like a large box, it weighs just 17 pounds and fits in the trunk of most cars.