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Fourth-Order Bandpass Subwoofer Enclosure Design Calculator

 This calculator will design a bandpass subwoofer enclosure to achieve a specific F3(L) . If you don't understand what this means, click here for help.
Calculate Your Enclosure Here
 This calculator will design an enclosure using any value for F3(L) that you desire. If the "Gain" value comes up negative, you will have to increase the value you entered for F3(L), or choose a higher S factor.

Note : Too much gain can be hazardous to your speakers, try to keep it +3 dB or less unless you want to find out what your speakers look like with holes in them. If the calculated gain is too high, enter a lower number in the desired F3(L) box. If the gain returns a negative value, enter a higher F3.
Number of Drivers 
Isobaric Loading

Yes  No
Enter Qts
Enter Vas  (ft3 )
Enter Fs

Choose an S Factor

0.7  0.6   0.5

Enter Desired F3(L) 
Vf =(ft3 )
Vr(ft3 )
Fb = Hertz
Passband Hertz
Gain = (dB SPL@1W/1M)

  If you want to experiment with different quantities of drivers, or the isobaric option, you don't need to enter all of the values again, just change the value you want to adjust and click the "Calculate Enclosure" button again. When you are finished, write down your enclosure specifications, (or copy & paste them), and go here to design the port(s) for your front chamber.

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