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Sealed Speaker Enclosure Design Calculator

 This calculator will design a "sealed" speaker enclosure to obtain a specific Qtc value. If you don't understand what this means, click here for help.
Calculate Your Enclosure Here
 To use this form, enter the Qts, Vas, and Fs parameters for your speaker, and then enter your desired Qtc in the boxes below. Then click the "Calculate Enclosure" button, and the results will appear in the empty text boxes. If the calculated F3 (-3 dB point) is too high you will need to enter a lower value for desired Qtc. A Qtc value of 0.707 will give you the lowest possible F3 for the woofer or subwoofer you are using. This is a maximally flat alignment. The drawback is a larger enclosure. F3 increases for Qtc values higher than 0.707, below that it increases again.
 Note: Typical Qtc values for designs that are commonly available are from 0.9-1.2. This means that most designs you have heard (unless you are listening at high-end audio retailers) are likely to have a peak in frequency response in the 70-120 Hz range. Many people like this and will be disappointed by the sound of a speaker without this "boost" in the bass.
Number of Drivers : Isobaric
Yes  No
Enter Qts
Enter Vas  (ft3 )
Enter Fs Hertz
Enter Qtc
Vb =  (ft3 )
 F3 = Hertz

  If you want to experiment with different quantities of drivers, or the isobaric option, you  don't need to enter the values again, just change the value you want to adjust and click the "Calculate Enclosure" button again.

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