michael chuaMay 6, 2018PRO DRIVERS12", Altec Lansing, CD912, Coaxial Altec Lansing CD912-8A Thiele / Small Parameters Sealed Box 55 liters. F3=74Hz, Q=0.86 Sealed Box 100 liters. F3=70Hz, Q=0.71 Sealed Box 150 liters. F3=72Hz, Q=0.63 Ported Box 75 liters. F3=60Hz Ported Box 100 liters. F3=50Hz Ported Box 150 liters. F3=43Hz