PR’s Data (old):

Fs = 26.00 Hz
Qms = 6.9900
Qes = 0.3900
Qts = 0.3694
Vas = 222.29 Liters
Cms = 5.427E-4 M/N
Re = 3.20 Ohms
BL = 9.62 N/A
Sd = 0.0540 Sq. Meters
Mms = 0.06904 Kg
Ref Efficiency = 0.963 %
Predicted Output = 92.04 dB/1W/1M
Predicted Sensitivity =  96.02 dB/2.83v/1M
Xmax = 7.37 mm