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Subwoofer Box Design

Designing the box has been a very difficult problem. The math isn't complicated, and is easily done with a spread sheet, but unfortunately I can't seem to make the box as small as I'd like to. This, of course, is because I'm building a bandpass box. But, I'm more willing to compromise on the size of the box than I am to compromise on the type. Building a bandpass box means that I can keep my speakers enclosed and protected. I hope to make the box look inconspicuous and easy to pack stuff on top of. Having two exposed 10" woofers doesn't accomplish either of those goals very well.

So, I'll be using a 3-chamber bandpass with 2 sealed sections and 1 vented section. I'll have 4 slot ports on my vented section. Here are my calculations:

Box Calculations for Fl
Vas 101.14 l
Fs 30.5 Hz
Qts 0.445
S 0.7
b 0.7206
Fl 42 Hz
Fl' 0.6127868852459
Fh 91.3894382022472 Hz
Qbp 0.90392587983616
Fb 61.9544704157366 Hz
Vf 39.25536706 * 2 l
Vr 32.3528344267576 l
Pa 4.0904342524327 dB

Port Calculations
Dv 11.9896857473094 cm
Fb 65.5 Hz
Vb 78.51073412 l
Lv 31.4475560689208 cm
Np 4
k 0.732

These numbers do not take into account the volume of the ports or the speakers. Once they're available, I'll post drawings which will include the final dimensions.

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