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LF21N551

WOOFER

The LF21N551 is very high power handling 21” neodymium woofer. The combination of a 3600 Watt power handling and a minimum weight of 13,7 Kg makes this transducer a unique product in his category.

The transducer design is based on a very strong neodymium magnetic structure and a new 5,3” inside-outside copper coil. 

The new Dual forced design provide an excellent heat dissipation and lower power compression. Special air-forced ventilations are provided for voice coil, magnet assembly and basket. The combination of carbon fibre loaded cone assembly, large triple roll surround, double silicon spider provides to the LF21N551 remarkable strength and best control under large excursion conditions.

A fully optimised T-pole design generate the minimum amount of flux modulation offering a peak to peak excursion of 72 mm. 

 

The waterproof  body cone treatment and polycotton surround ensure a durable performance in every application.

Applications
  • • The LF21N551 is ideal in applications where combinations of maximum power handling, light weight and ultra fast time response are required.
  • • Perfect for powerful lows in horn loaded sub bass systems or reflex designs.
  • • Ideal for touring, find a perfect application in high power, heavy duty, club subwoofer systems.
Part Number
  • • 11100076
Features
  • 5.3 - inch Inside/Outside copper voice coil
  • 4000 Watt continuous program power handling
  • 97 dB Sensitivity
  • 30 Hz - 1 kHz Frequency range
  • Dual-forced air ventilation for minimum power compression
  • Dual spider designed with silicon based damping control
  • BL of 39 Txm to provide a faster and accurate low frequency
General Specifications
  • Nominal Diameter: 530 / 21 mm/inch
  • Rated Impedance: 8 Ω
  • Program Power: 4000 W AES
  • Power handling capacity: 2000 W AES
  • Sensitivity: 97 dB
  • Frequency Range: 30 Hz ÷ 1000 Hz
  • Effective Piston Diameter: 470 / 18.5 mm/inch
  • Max Excursion Before Damage (peak to peak): 72 / 2.83 mm/inch
  • Minimum Impedance: 7.1 Ω
  • Voice Coil Diameter: 135 / 5.3 mm/inch
  • Voice Coil Material: Copper
  • Voice Coil Winding Depth: 39 / 1.54 mm/inch
  • Number of layers: 2
  • Kind of layer: inside / outside
  • Top Plate Thickness: 18 / 0.71 mm/inch
  • Cone Material: No pressed pulp carbon fiber reinforced
  • Cone Design: Curved
  • Surround Material: Polycotton
  • Surround Design: Triple roll
Thiele/Small Parameters
  • Resonance frequency: 35 Hz
  • DC resistance: 5.2Ω
  • Mechanical factor: 6.2
  • Electrical factor: 0.35
  • Total factor: 0.33
  • BL Factor: 39 T · m
  • Effective Moving Mass: 434 g
  • Equivalent Cas air load: 200 liters
  • Effettive piston area: 0.173
  • Max. linear excursion (mathematical): 15 mm
  • Voice - coil inductance @ 1kHz: 3.2 mH
  • Half-space efficiency: 2.40%
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: 245 / 9.65 mm/inch
  • Volume occupied by the driver: 7.2 / 0.25 liters/ft³
  • Net Weight: 13.7 / 30.2 kg/lbs
Shipping information
  • Shipping weight: 15.2 / 33.51 kg/lbs

The data are not binding; RCF reserves the right to modify the data at any time and without previous notice.

The data are not binding; RCF reserves the right to modify the data at any time and without previous notice.