📦 BOX SIZE CALCULATOR
Calculate the optimal enclosure volume for your subwoofer. Whether you want sealed or ported, this tool tells you exactly how big your box should be based on your sub’s specs.
Suggested External Dimensions (in inches)
*These are general recommendations. Always check your subwoofer manufacturer’s specs for optimal enclosure volume.
📋 General Box Size Guidelines
🔇 Sealed Enclosures
🔊 Ported Enclosures
*These are general guidelines. Always check your subwoofer’s manual for manufacturer-recommended enclosure volumes.
📐 How to Measure Your Box
Calculate Volume
Internal volume = Width × Height × Depth (in inches) ÷ 1728 = cubic feet
Account for Displacement
Subtract volume taken by subwoofer, port, and bracing from internal volume for accurate net volume.
External Dimensions
Add 2× material thickness to each dimension. For 3/4″ MDF, add 1.5″ to width, height, and depth.
❓ Box Size FAQ
What’s the difference between sealed and ported?
Sealed boxes are smaller, have tighter more accurate bass, and roll off gradually. Ported boxes are larger, have more output (3-5dB louder), but have less control and can sound boomy. Choose sealed for SQ, ported for SPL.
Can I use a bigger box than recommended?
Going slightly larger (10-20%) can increase low-end output but reduces power handling. Too large and you risk bottoming out the sub. Smaller boxes handle more power but have less low-end extension.
What thickness MDF should I use?
3/4″ MDF is standard for most boxes up to 3 cu ft. For larger boxes or high-power applications, use double baffle (1.5″) or 1″ MDF. Always use MDF—never particle board or plywood.
Do I need to add bracing?
For boxes over 2 cu ft, bracing is recommended to prevent panel flex. For 3+ cu ft, it’s essential. Use 2×2 wood dowels or fiberglass resin in corners. Account for bracing volume in your final calculations.
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