Media
Auto-advancing
Size
21"
Impedance
1Ω
RMS Power
5000W
Sensitivity
99dB
EBP
168
Vented alignment
Vd
3696cm³
Frequency response
Manufacturer-provided response plots and related charts.
T/S Parameters
Valid
Fs37Hz
Qts0.21
Qes0.22
Qms4.9
Vas155.0L
Re0.7Ω
Le0.50mH
BL19.1Tm
Sd1680cm²
Mms487g
Xmax22.0mm
SPL99dB
Power5000W
Power Nominal2500W
Impedance1Ω
Min Impedance1.1Ω
F Low37Hz
F High1000Hz
Voice Coil153mm
Flux Density1.35T
Pricing & availability
Price movement
Other offers
1 vendorjpleisure
Updated 17 May 2026
Source: ex VAT · 20%
£1,015.85
inc VAT
Best current price
Updated 17 May 2026
bluearan
£750.00
Avg £882.92£132.92 below avg (-15.1%)
inc VAT
Dimensions & Physical
Weight23.0kg
Diameter547.0mm
Overall Depth269.0mm
Cutout Diameter508.0mm
Bolt Circle Diameter527.0mm
Additional Manufacturer Specs
Bl19.1 Tm
Fs37 Hz
Le0.5 mH
Re0.7 Ω
Sd1680 cm² (260.4 in²)
Ebp168 Hz
Mms487 g
Qes0.22
Qms4.9
Qts0.21
Vas155 dm³ (5.47 ft³)
η03.2 %
ConeRCK21IPAL
Xmax22 mm
Xvar15 mm
SpiderDouble Silicone
Cone ShapeRadial
Pole DesignT-Pole
Winding Depth48 mm (1.9 in)
Surround ShapeTriple Roll
Former MaterialGlass Fibre
Magnet MaterialNeodymium Inside Slug
Nominal Diameter530 mm (21 in)
Winding MaterialAluminium
Magnetic Gap Depth18 mm (0.7 in)
Recommended Tuning40 Hz
Bolt Circle Diameter527 mm (20.7 in)
Recommended Enclosure200 dm³ (7.06 ft³)
Woofer Cone TreatmentTWP Waterproof Both Sides
Baffle Cutout Diameter508 mm (20 in)
Flange And Gasket Thickness13 mm (0.51 in)
Air Volume Occupied By Driver16 dm³ (0.56 ft³)
Similar Drivers
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Reference
B&C
21IPAL
21"
Best current price
£750.00
Compare on
Only active params are shown here. Size stays fixed automatically.
5 active T/S params, plus size.
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