RCF LF21X451 21-inch Sub Woofer 2000 Wrms 4000 Watts Max 4.5" Fiberglass Inside | Outside Copper Voice Coil Dual Forced Air Vent 8 OhmFEATURES || 4.5 - inch fiberglass Inside/Outside copper voice coil || 4000 Watt continuous program power handling || 97 dB Sensitivity || 28 Hz - 1 kHz Frequency range || Dual-forced air ventilation for minimum power compression || Dual spider designed with silicon based damping control || BL of 30.5 Txm to provide a faster and accurate low frequency ||GENERAL SPECIFICATIONS || Nominal Diameter : 530 / 21 mm/inch Rated Impedance : 8 Ohm || Program Power : 4000 W AES || Power handling capacity: 2000 W AES || Sensitivity : 97 dB || Frequency Range : 28 Hz ÷ 1000 Hz || Effective Piston Diameter : 470 / 18.5 mm/inch || Max Excursion Before Damage (peak to peak) : 54 / 2.12 mm/inch || Minimum Impedance : 6.7 Ohm ||GENERAL SPECIFICATIONS || Voice Coil Diameter : 115 / 4.5 mm/inch || Voice Coil Material : Copper || Voice Coil Winding Depth : 34 / 1.33 mm/inch || Number of layers : 2 || Kind of layer : inside / outside || Top Plate Thickness : 15 / 0.6 mm/inch || Cone Material : No pressed pulp || Cone Design : Curved || Surround Material : Polycotton || Surround Design : Triple roll ||PARAMETERS || Resonance frequency: 28 Hz || DC resistance: 5.4 Ohm || Mechanical factor: 6.9 || Electrical factor: 0.39 || Total factor: 0.37 || BL Factor: 30.5 T · m || Effective Moving Mass: 355 g || Equivalent Cas air load: 385 liters || Effective piston area: 0.173 m² || Max. linear excursion (mathematical): 13.5 mm || Voice - coil inductance @ 1kHz: 2.9 mH || Half-space efficiency: 2.2% ||MOUNTING INFORMATION || Overall Diameter: 547 / 21.5 mm/inch || Bolt Circle Diameter: 527 / 20.7 mm/inch || Bolt Hole Diameter: 6.5 / 0.25 mm/inch || Front Mount Baffle Cut-out: 512 / 20.1 mm/inch || Rear Mount Baffle Cut-out: 512 / 20.1 mm/inch || Depth: 230 / 9.05 mm/inch || Volume occupied by the driver: 6.5 / 0.229 liters/ft³ || Net Weight: 15.5 / 34.0 kg/lbs || SHIPPING INFORMATION || Shipping weight: 17.59 / 26.6 kg/lbs
