21-in Low Distortion 3400 Watt Woofer 4 Ohms w/Neodymium magnet

3400 W continuous program power capacity .: 116 mm 4.5 in split winding copper voice coil .: 33 - 1000 Hz response .: 97 dB sensitivity .: 60 mm peak-to-peak excursion before damage .: Neodymium magnet allows a very high force factor and linear excursion .: Double silicone spider with optimized compliance .: Ventilated voice coil gap for reduced power compression.: Aluminium demodulating ring for very low distortion Nominal Diameter: 530 mm 21.0 in Nominal Impedance: 4 Ohms Minimum Impedance: 4.2 Ohms Nominal Power Handling: -see notes: 11700 W Continuous Power Handling: -see notes: 23400 W Sensitivity: -see notes: 397.0 dB Frequency Range: 33 - 1000 Hz Voice Coil Diameter: 116 mm 4.5 in Winding Material: Copper Former Material: Glass Fibre Winding Depth: 34.0 mm 1.34 in Magnetic Gap Depth: 14.0 mm 0.55 in Flux Density: 1.15 T Surround Shape: Triple Roll Cone Shape: Radial Magnet Material: Neodymium Inside Slug Spider: Double Silicone Pole Design: T-Pole Woofer Cone Treatment: TWP Waterproof Both Sides Recommended Enclosure: 250.0 dm 3 8.83 ft 3 Recommended Tuning: 32 Hz Parameters -see notes: 4 Resonance Frequency: 33 Hz Re: 3.6 O Qes: 0.37 Qms: 7.7 Qts: 0.36 Vas: 278.0 dm 3 9.7 ft 3 Sd: 1680.0 cm 2 260.4 in 2 ?0: 2.6 % Xmax: +/- 14.0 mm Xvar: +/- 15.0 mm Mms: 335.0 g Bl: 24.8 Txm Le: 1.7 mH EBP: 89 Hz Mounting and Shipping Info Overall Diameter: 547 mm 21.5 in Bolt Circle Diameter: 527 mm 20.7 in Baffle Cutout Diameter: 503.0 mm 19.8 in Depth: 249 mm 9.8 in Flange and Gasket Thickness: 14 mm 0.53 in Air Volume Occupied by Horn: 15.0 dm 3 0.53 ft 3 Net Weight: 14.0 kg 30.8 lb Shipping Units: 1 Shipping Weight: 16.3 kg 35.94 lb Shipping Box: 570x570x320 mm 22.44x22.44x12.60 in