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Fourth-Order Bandpass Subwoofer Enclosure Design Calculator

 This calculator will design a bandpass subwoofer enclosure to achieve a specific amount of gain (in dB). If you don't understand what this means, click here for help.
Calculate Your Enclosure Here
 This Javascript is designed to calculate a bandpass enclosure with any amount of gain that you desire. If the F3L is too high, try a higher S factor. If this still gives you a F3L that is too high, you will have to reduce the amount of gain you are asking for, or use a different speaker.

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.
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 Gain  dB
Vf =(ft3 )
Vr(ft3 )
Fb = Hertz
Passband Hertz

  If you want to experiment with different quantities of drivers, or the isobaric option, you don't have 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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