The Subwoofer DIY Page v1.1
Sealed Systems: Frequency Response Calculations
last updated:13 April 2011
To calculate the frequency response of a sealed enclosure system, you will need to know the following:

   Fb = resonance frequency of the system
   Qtc = Final Q of the system at resonance


then,

   Fr = (F/Fb)^2
   dBmag = 10*LOG(Fr^2/((Fr-1)^2+Fr/Qtc^2))

where,

   F = frequency (Hz)
   dBmag = SPL 1W/1M at frequency F