Subwoofer Box Calculator
Sealed Box Volume
Calculate sealed enclosure internal volume and dimensions
Ported Box & Port Length
Calculate port dimensions for a ported (bass reflex) enclosure
Formula
Port Length = (23562.5 x Port Area) / (Fb^2 x Volume) - 0.825 x Port Diameter | Port Area = pi x (D/2)^2 | 1 cu ft = 1728 cu in = 28.32 liters
Frequently Asked Questions
Sealed vs ported subwoofer box: which is better?
Sealed boxes produce tighter, more accurate bass with a gentle roll-off and are easier to build. Ported boxes are louder and extend deeper but require precise port tuning. Sealed is better for music accuracy; ported for maximum SPL.
What volume box do I need for a 12 inch subwoofer?
A typical 12" subwoofer needs 0.75-2.0 cubic feet for a sealed box, or 1.5-3.0 cubic feet for a ported box. Always check the manufacturer's Thiele-Small parameters for optimal volume.
What wood should I use for a subwoofer box?
3/4" MDF (Medium Density Fiberboard) is the most popular choice for subwoofer enclosures. It's dense, affordable, and damps vibrations well. Plywood is lighter and stronger but more expensive. Avoid particle board.
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