Power Rating Watts 450W Music Program 900W Resonance 31Hz Usable Frequency Range 63Hz-2.8kHz Sensitivity 98.1 Magnet Weight 80 ounce Gap Height 0.375", 9.53mm Voice Coil Diameter 3", 76.2mm THIELE and SMALL PARAMETERS Resonant Frequency (FS) 31Hz DC Resistance (Re) 3.68 Coil Inductance (Le) 0.88mH Mechanical Q (QMS) 10.14 Electromagnetic Q (QES) 0.25 Total Q (QTS) 0.25 Compliance Equivalent Volume (Vas) 329.9 liters / 11.7 cu.ft. Peak Diaphragm Displacement Volume (VD) 206cc Mechanical Compliance of Suspension (CMS) 0.35mm/N BL Product (BL) 14.7 T-M Diaphragm Mass Inc. Air load (Mms) 77 grams Efficiency Bandwidth Product (EBP) 124 Maximum Linear Excursion (XMAX) 2.4mm Surface Area of Cone (SD) 856.3 cm2 Maximum Mechanical Limit (XLIM) 11.6mm MOUNTING INFORMATION Recommended Enclosure Sealed Vented 40-79 liters/1.4-2.8 cu.ft. Overall Diameter 15.16", 384.9mm Baffle Hole Diameter 13.77", 349.6mm Front Sealing Gasket fitted as standard Rear Sealing Gasket fitted as standard Mounting Holes Diameter 0.25", 6.4mm Mounting Holes B.C. D. 14.56", 369.9mm Depth 6.13", 156mm Net Weight 17.6 lbs., 8 kg Shipping Weight 19.8 lbs., 9 kg MATERIALS OF CONSTRUCTION Coil Construction Copper voice coil Former Polyimide former Magnet Composition Ferrite magnet Core Details Vented core Basket Materials Pressed steel basket Cone Composition Paper Cone Edge Composition Cloth cone edge Dust cap Composition Solid composition paper dust cap