Basic formulas for cabinet design

[audfrknaveen]

Dear all,

The following are the formulas i came across for BASS REFLEX enclosures.

Box volume Vb=15 Vas (Qts^2.87)
3dB down point F3=0.26 (Fs)/(Qts^1.4)
Box tuning Fb=0.42 (Fs)/(Qts^0.9)

Can anyone share similar formulas for Sealed enclosure please ???

We have to do detailed simulation any way.....but these formulas come handy in selecting drivers quickly.
Hope this thread helps me and others as well...
If any corrections are there in the formulas...they are most welcome.

Regards,
AudfrkNaveen

 

[audfrknaveen]

And just to add people ... those above formulas are for Maximally flat response in bass reflex. For extended bass or high spl etc, the formulae might change. I am not aware.

If someone can give basic formulae for port size and length, that will be great too ...

 

[midrange]

Go to lalena.com, click on diy audio and video, find speaker box designer. Just input the vas, qts, and Fs of any drive unit. You can try sealed box, or butterworth ported. It will give box volume. .707 for Qb is a standard maximally flat value. But, I believe that .5 is the absolute optimum for a sealed box. Someone with more knowledge than me could advise better.

 

[audfrknaveen]

thanks a lot midrange