Dual driver vented enclosure ~ calculator

Dual driver vented enclosure

   This system uses the Butterworth 3rd order 2-way crossover to produce a quasi- spherical vertical response pattern. A dimension ratio of 1: 1.618: 0.618 provides cancellation of resonating frequencies inside the enclosure. Port, driver, and tweeter should be centered vertically so they are in phase with the listener's ear.

   First enter driver parameters.

   Then enter volume of enclosure to calculate performance specifications.  If only Qms and Qts are known, press "Qts" button to calculate Qts.  Qms and Qes are optional. Fs, Qts and Vas  must be entered.




Enter Dia :   cm The diameter1 across the speaker cone.
Enter Fs :   Hz The resonant frequency  of the driver.
Enter Qms :   Q mechanical
Enter Qes :   Q electrical
Enter Qts :   The total Q of the driver.  
Enter Vas :   liters The equivalent volume of air having the same compliance as the suspension system of the driver.

   Volume and port dimensions are recommended for optimum performance.  However, they can be changed to calculate performance specifications for different size ports and enclosures.  Enter different volume and port dimensions if desired.  Enter volume of internal driver and parts.  Calculate performance specifications before calculating port dimensions.

Enter Vdr : liters Volume of internal driver and parts
Enter Dp : cm Diameter of port(s)
Enter  V b : liters Estimate volume for the enclosure


Width =    cm 
Height =    cm 
Depth =    cm 


 diameter(s) =    cm 
 length(s) =    cm 
encl2.gif (4256 bytes)
   The distance between drivers (dd) is dependant upon the crossover frequency of the Butterworth 3rd order 2-way crossover.

enter crossover frequency :   Hz       cm

Performance specifications





Fb =   Hz Resonance frequency of tuned port.
Peak db =   db Peak decibel at resonance. 
F3 =   Hz The " cut off " frequency  at -3db.

   1The measurement is the diameter across the total physical "moving" cone of the driver.

   2The dimensions are "inside" measurements which are calculated to provide the enclosure volume needed.