box size question

[audiofx81]

Ok guys i never made my own box before but i picked up some MDF and i would like to try. When a sub require say 1 cuft of space, i can just make a square box 1ft long 1 ft wide 1 ft deep 1 ft high? Or must i take into account how much of that space the magnet takes? the small spot in my trunk by the back seats is 40" wide and 16" deep. i plan on doing my sub amp and enclosure in one.

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| amp | SUB|
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[squeak9798]

You need to take into account the displacement of the sub inside the box. So, if you need 1cuft net for that a sub that has .15cuft of displacement, you need to build a box with a gross internal volume of 1.15cuft, which would work out to be 13" x 12.75" x 12" internally (or, using .75" MDF, 14.5" x 14.25" x 13.5" external dimensions)