Description
The RCF LF21X451 is a premium 21-inch subwoofer built for ultra-high-output low-frequency performance. Featuring a robust 4.5-inch inside/outside copper voice coil, dual-forced air ventilation, and a fiber-loaded cone, this transducer delivers deep bass, exceptional linearity, and maximum reliability. With 4000W program power handling and high excursion capability, it’s engineered for demanding professional audio applications requiring both punch and precision.
Product Specifications:
Nominal Diameter: 21"
Rated Impedance: 8 ohm
Program Power: 4000 W
Power Handling (AES): 2000 W
Sensitivity: 97 dB
Frequency Range: 28 Hz – 1 kHz
Voice Coil Diameter: 4.5"
Voice Coil Material: Copper
Voice Coil Design: Inside/Outside, 2 layers
Voice Coil Length: 1.34"
Magnet Type: Ceramic
Top Plate Thickness: 0.59"
BL Factor: 30.5 T·m
Inductance (1 kHz): 2.90 mH
Mechanical
Cone: Fiber-loaded, curved design
Surround: Triple-roll polycotton
Spider: Dual with silicon-based damping
Max Excursion (Before Damage): 2.13"
Xmax (Linear Excursion): 0.55"
Thiele-Small Parameters
Resonance Frequency (Fs): 28 Hz
DC Resistance (Re): 5.40 ohm
Qms: 6.90
Qes: 0.39
Qts: 0.37
Moving Mass (Mms): 355 g
Vas: 385 L
Sd: 0.170 m²
Efficiency (Half-space): 2.20%
Mounting Information (Inches)
Overall Diameter: 21.54"
Bolt Circle Diameter: 20.75"
Bolt Hole Diameter: 0.28"
Baffle Cut-out (Front/Rear): 20.16"
Driver Depth (Height): 9.65"
Driver Volume Occupied: 0.26 ft³
Dimensions & Weight
Height: 9.65"
Diameter: 21.54"
Weight: 34.17 lbs
Package (H x W x D): 11.18" x 22.99" x 23.78"
Shipping Weight: 40.79 lbs
Get the gear you need now with easy financing
Get the gear you need now with Financing and Lease options. As an artist or sound professional your business needs high quality speakers, lighting and cases to do your job, be professional and competitive.
Choose Shop Pay or After Pay in checkout for instant financing application. We also offer Acima Leasing, Synchrony, Progressive or Snap financing just give us a call 1-800-700-4542.
*Our online prices are always honored instore guaranteed.
Military & First Responder Discounts
We're proud to support those who serve. Active-duty military, veterans, and first responders qualify for a special discount on your gear. See our Military Discount details here and how to redeem.