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18 SOUND 21 NLW 9001

18 SOUND 21 NLW 9001

The 21NLW9001 is an ultra low frequency 21 inch neodymium high performance transducer. The transducer is the evolution of the 21NLW9000 subwoofer, and has been optimized for direct radiation and bandpass subwoofer cabinet designs. 

More Information

  • 95 dB SPL 1W / 1m average sensitivity
  • 135 mm (5.3 in) Interleaved Sandwich Voice coil (ISV)
  • 3600W program power handling
  • 60mm peak to peak excursion
  • Ultra linear dual magnet motor design
  • Single Demodulating Ring (SDR) for lower distortion
  • Composite reinforced straight ribbed cone
  • Optimized high grade ferrite magnet assembly
  • Recommended for subwoofer usage in compact vented enclosures

Technical Specification



nominal diameter 533mm (21in)
Rated Impedance 8 ohms
AES power 1800W
program power 3600W
peak power 10000W
sensitivity 98dB
frequency range 25 - 1500Hz
Power Compression @-10dB 0.7dB
Power Compression @-3dB 1.5dB
Power Compression @ Full Power 2.2dB
Max Recomm. frequencies 150Hz
recommend EnclosureVolume 120 ÷ 500 lt (4.24 ÷ 17.7 cuft)
minimum impedance 7.6 ohms at 25°C
Max peak-to-peak excursion 70mm (2.75in)
Voice coil diameter 135mm (5.3in)
Voice coil technology split winding, 4 layers copper wire
suspension Triple roll, polycotton
cone Straight ribbed carbon fiber loaded cellulose

Thiele Small Parameters

Fs 32Hz
re 5.9 ohms
sd 0.1662 (257.6
sqm 4.5
Qes 0.34
Qts 0.31
vase 244 lt. (8.62 cuft)
Mms 390 gr. (0.86 lb)
BL 37 tm
Linear Mathematical Xmax ±14mm (±0.55in)
Le (1kHz) 3.1mH
Ref. Efficiency 1W@1m (half space) 95.5dB

Mounting information

Overall diameter 545mm (21.46in)
N. of mounting holes and bolt 8th
Mounting holes diameter 8.5mm (0.33in)
Bolt circle diameter 520mm (20.47in)
Front mount baffle cutout ø 492mm (19.37in)
Rear mount baffle cutout ø 490mm (19.29in)
Total depth 250mm (9.8in)
Flange and gasket thickness 18mm (0.7in)
Net weight 14kg (30.9lb)
Shipping weight 15.5kg (34.2lb)
Cardboard packaging dimensions 570x570x290mm (22.4x22.4x11.4in)


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