21" | 21NPW
Neodymium Woofer
Key features:
- 5.3” DIAMETER VOICE COIL, HIGH POWER HANDLING
- 3600 WATTS PROGRAM POWER HANDLING
- TRIPLE SILICONE SPIDER, HEAVY DUTY FIBER REINFORCED CONE WITH LARGE SURROUND
Design notes:
The 21NPW is a high efficiency, (97 dB 1watt / 1 meter) 21-inch woofer with incredibly linear frequency response characteristics, extreme high power handling capability while generating low harmonic distortion artifacts. The 21NPW uses a lightweight carbon fiber loaded cone assembly along with a high excursion triple roll constant geometry surround. This combination provides remarkable strength, high efficiency and a peak to peak maximum excursion of 50mm (2in). Power HandlingAt the core of the 21NPW is it’s voice coil technology featuring a composite Polyimide former material capable of withstanding peak temperatures in excess of 350C, well beyond the thermal requirements of modern professional audio systems. The 21NPW delivers incredible performance. REDCATT has implemented a triple layer/silicone spider design to ensure long term Fs memory, consistency and diminish anomalies associated with spider deterioration.
Specifications:
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General specs |
Nominal Diameter: | 21 in. |
Rated Impedance: | 4 Ohm |
Power handling |
AES Power: | 1,800 Watts |
Program Power: | 3,600 Watts |
Voice Coil |
Diameter: | 5.3 in. |
Winding wire: | Copper |
Former: | Glass-fiber |
Winding height: | 33 mm |
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T/S Parameters |
Resonant frequency: | 35 Hz |
Re: | 3 ohm |
Qes: | 0.33 |
Qms: | 11.12 |
Qts: | 0.32 |
Vas: | 149 liters |
Sd: | 1,662 cm2 |
Mms: | 514 grams |
Bl: | 32.9 |
Le: | 1.14 mH |
Sensitivity: | 96.32 dB |
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Design details |
Surround Material: | Fabric |
Cone material: | Paper |
Spider: | Nomex |
Plate thickness: | 15 mm |
Peak to peak linear cone Displacement | 15.5 mm |
Overall diameter: | 546 mm |
Bolt circle diameter: | 520 mm |
Baffle cutout dia.: | 496 mm |
Number of mounting holes: | 8 |
Depth (flange to rear): | 245 mm |
Net weight: | 14.85 kg |
Ordering codes: |
4 ohm version: | 21NPWX4-018 |
8 ohm version: | 21NPWX8-018B |
16 ohm version: | n/a |
Recone kits: |
4 ohm version: | RC21NPWX4-018 |
8 ohm version: | RC21NPWX8-018B |
16 ohm version: | n/a |
Frequency response & lmpedance
2D drawing