How to figure out internal volume after displacement?

[hzsogood]

My box is 15h x 33w x18d , which is 4.06 cf internal volume.. My port is 3" x 23" and the subs ( 2 12 lvl 3s ) are .15 .. So, Just wondering how everything kind of fits together mathematically

[OBI]

Just use torres' calculator it will make it easier for you. But if you want to do it by hand just subtract your dis. vol from your gross box vol. And also if those are outter dimensions then subtract 1.5 from each one, for wood thickness (if using 3/4 sheets).

[Autruche]

measure your box in inches, subtracting the thickness of the wood, multiply the dimensions, and divide that by 1728 (1728 cubic inches in 1 cubic foot.) do the same for you port, but don't subtract the wood thickness. subtract port volume from the box volume and then subtract your subs displacement, which can be found on the website or the specs sheet you got with it. your leftover amount is volume after displacements. If you have bracing done, be sure to get the volume of that calculated out(IE: 2x2 23 inches long is 92 cubic inches, blah blah blah) and subtract that from the initial box volume. Hope that helps.

[Torres]

depending on how many walls your port is will determine what dimensions you use for port volume. for example a port with 3 independent sides will have a different displacement than a port with 1 independent side. keep that in mind. will it make much of a difference? maybe not, but precision is fun

[Bumpin the TWP]

Just use torres' calculator it will make it easier for you. But if you want to do it by hand just subtract your dis. vol from your gross box vol. And also if those are outter dimensions then subtract 1.5 from each one, for wood thickness (if using 3/4 sheets).

I'd just use Torres' calculator, i make tons of sub boxes and it makes it easy.