Speaker Enclosure Volume Calculator
Enter Thiele-Small parameters to get optimal sealed and ported enclosure volumes, predicted -3dB frequency, and port dimensions. Driver presets for common subwoofer sizes. Nothing uploaded.
Driver Parameters
Port Settings (ported box)
Enclosure Results
Results based on standard B4 (Butterworth) alignment. Always verify with acoustic simulation software before building.
Learn more: speaker enclosure design
FAQ
How do I calculate speaker box volume?
For a sealed box, optimal volume is approximately Vas / (Qtc²/Qts² - 1) where Qtc = 0.707 for Butterworth response. For a ported box, a common starting point is Vb = 15 × Vas × Qts^3.3. These are starting points - final tuning should be done with acoustic simulation software.
What Qts is best for sealed vs ported?
Qts below 0.3 works best in ported enclosures. Qts between 0.3 and 0.5 can work in both sealed and ported. Qts above 0.5 generally works best in sealed enclosures or infinite baffle. Very high Qts (above 0.7) drivers are designed for very large sealed boxes.
What are Thiele-Small parameters?
Thiele-Small parameters describe the electromechanical properties of a speaker driver needed for enclosure design: Vas (equivalent compliance volume in litres), Qts (total Q factor combining mechanical and electrical damping), and Fs (free-air resonant frequency in Hz). Find them on the driver's datasheet.