B&C 21DS115-4 Specifications
Lightweight but powerful FEA-optimized neodymium magnet
Extremely high BL factor and Xmax for outstanding LF output
14 mm Xmax, 60 mm peak-to-peak excursion before damage
4.5" split winding copper voice coil on fiberglass former
Ventilated voice coil gap reduces power compression
Aluminum demodulation ring on pole piece reduces distortion
Double silicone spider
Nominal diameter: 530 mm (21.0 in)
Nominal impedance: 4 Ohm
Minimum impedance: 4.2 Ohm
Nominal power handling: 1700 W
Continuous power handling: 3400 W
Sensitivity (1W/1m): 97.0 dB
Frequency range: 33 - 1000 Hz
Voice coil diameter: 116 mm (4.5 in)
Winding material: Copper
Former material: Glass Fibre
Winding depth: 34 mm (1.34 in)
Magnetic gap depth: 14 mm (0.55 in)
Flux density: 1.15 T
Design
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 dm3 (8.83 ft3)
Recommended tuning: 32 Hz