RCF LF21N451 - 21" 1500W 8 Ohm Speaker Driver Woofer

Description:

Please note this is for one driver, image shows front and back.

The LF21N451 is a high-power 21" low-frequency transducer engineered for demanding subwoofer applications requiring extreme output, efficiency, and precision. Designed to deliver powerful and accurate sub-bass performance, it is ideal for large-scale sound reinforcement systems, touring rigs, and high-performance installations.

At the heart of the driver is a 4.5" inside/outside copper voice coil, optimised for high excursion and improved linearity at very low frequencies. The cone is constructed from an advanced carbon fibre, nylon, and cellulose composite, providing exceptional rigidity and resistance to deformation under high pressure. Combined with a triple-roll surround and dual spider system with silicon-based damping, the driver maintains precise control even at extreme excursion levels.

The LF21N451 also features a dual-forced air ventilation system to minimise power compression and ensure efficient cooling during high-output operation. A neodymium magnet structure and optimised T-pole design contribute to improved efficiency and reduced flux modulation, resulting in fast, accurate low-frequency reproduction with minimal distortion.

Features:

Type: 21" High-Power Subwoofer Driver

Power Handling: 1500W RMS / 3000W Program
Sensitivity: 98.5 dB

Voice Coil: 4.5" Copper Voice Coil (Inside/Outside Winding)
Cone: Carbon Fibre / Nylon / Cellulose Composite

Surround: Triple-Roll Polycotton Surround
Design: Dual Spider with Silicon-Based Damping

Cooling: Dual-Forced Air Ventilation
Magnet: Neodymium

Performance: High Excursion Design with Low Distortion
BL Factor: 34.5 Tm for Fast, Accurate Low Frequencies

Application: High-performance subwoofers, touring systems, and large-scale PA

Specifications:

Nominal Diameter: 21" (533mm)
Impedance: 8Ω
Minimum Impedance: 7.1Ω

Frequency Response: 30Hz – 1000Hz
Resonance Frequency (Fs): 30Hz

Voice Coil Diameter: 114mm
Voice Coil Length: 34mm

Sensitivity: 98.5 dB
BL Factor: 34.50 Tm

Xmax: 13mm
Max Excursion (Peak-to-Peak): 58mm

Effective Piston Diameter: 470mm
Effective Piston Area (Sd): 0.170 m²

Mounting Diameter: 547mm
Bolt Circle Diameter: 527mm
Cut-Out: 512mm

Depth: 249mm
Weight: 10.9kg

Magnet Type: Neodymium
Surround Material: Polycotton

Compliance: CE