Eminence Professional Series Sigma Pro 18A-2 18" Bass Speaker, 650 Watts at 8 Ohms

Power Rating Watts 650W Music Program 1300W Resonance 28Hz Usable Frequency Range 41Hz-2.4kHz Sensitivity 99 Magnet Weight 120 ounce Gap Height 0.375", 9.53mm Voice Coil Diameter 3", 76.2mm THIELE and SMALL PARAMETERS Resonant Frequency (FS) 28Hz DC Resistance (Re) 6.29 Coil Inductance (Le) 1.90mH Mechanical Q (QMS) 8.28 Electromagnetic Q (QES) 0.30 Total Q (QTS) 0.29 Compliance Equivalent Volume (Vas) 441.2 liters / 15.6 cu.ft. Peak Diaphragm Displacement Volume (VD) 695cc Mechanical Compliance of Suspension (CMS) 0.24mm/N BL Product (BL) 22.1 T-M Diaphragm Mass Inc. Air load (Mms) 130 grams Efficiency Bandwidth Product (EBP) 93 Maximum Linear Excursion (XMAX) 6.1mm Surface Area of Cone (SD) 1140.0 cm2 Maximum Mechanical Limit (XLIM) 18.0mm MOUNTING INFORMATION Recommended Enclosure Sealed Vented 93-212 liters/3.3-7.5 cu.ft. Overall Diameter 18", 457.2mm Baffle Hole Diameter 16.56", 420.5mm Front Sealing Gasket fitted as standard Rear Sealing Gasket fitted as standard Mounting Holes Diameter 0.28", 7.1mm Mounting Holes B.C. D. 17.25", 438.2mm Depth 8.15", 207mm Net Weight 24.5 lbs., 11.1 kg Shipping Weight 28.1 lbs., 12.8 kg MATERIALS OF CONSTRUCTION Coil Construction Copper voice coil Former Polyimide former Magnet Composition Ferrite magnet Core Details Vented and extended core Basket Materials Die-cast aluminum basket Cone Composition Paper Cone Edge Composition Cloth cone edge Dust cap Composition Solid composition paper dust cap