21NDS151U1 Subwoofers 21 inchs

Notes

- 6 INCH COPPER VOICE COIL
 
- 97 dB/SPL SENSITIVITY
 
- 4400 WATT PROGRAM POWER HANDING
 
- FEM OPTIMIZED MOTOR AND SUSPENSIONS
 
- 53mm PEAK TO PEAK MAXIMUM EXCURSION
 
- OPTIMIZED COOLING SYSTEM
 
- ALUMINIUM DEMODULATING RING
 
- DOUBLE SPIDER
 
- RESONANCE FREE AND HEAVY DUTY BASKET DESIGN
 
- TRIPLE ROLL SURROUND

GENERAL SPECIFICATIONS

Nominal diameter 548(21) mm (in.)
Nominal impedance 4 Ω
Minimum impedance 4.5 Ω
Program power (1) 4400 W
AES Power rating(2) 2200 W
Sensitivity (3) 97 dB
Frequency range 29 ~ 1000 Hz
Voice coil diameter 151(6) mm (in.)
Chassis material Aluminium
Magnet material Neodymium
Magnet dimensions (ODxIDxh) 145 x 60 x 10 mm
Coil material SV
Former material Glass Fiber
Xmax(4) 15.8 mm
Xmech(5) 26.5 mm
Gap height 17 mm
Voice coil Winding height 40 mm

SMALL SIGNAL PARAMETERS

DC resistance(Re) 3.6 Ω
Resonance frequency(Fs) 29 Hz
Moving mass(Mms) 407 g
Compliance(Cms) 0.07 mm/N
Force factor(BL) 32 N/A
Mechanical Q-factor(Qms) 5.8
Electrical Q-factor(Qes) 0.35
Total Q-factor(Qts) 0.33
Equivalent air volume(Vas) 371 I
Voice coil Inductance(Le) 3.20 mH
Diaphragm area(Sd) 1750 cm2
Reference efficiency(Eta O) 2.9 %

SHIPPING INFORMATION

Net weight 22.1 Kg
Multipack size (1) (W x D x H) 570 x 570 x 307 mm
Multipack weight 24.6 Kg

OTHERS

(1)Program power is defined as 3 dB greater than AES Power.
(2) Tested for two hours using a continuous, band-limited pink noise signal as per AES 2-1984 Rev. 2003. Loudspeaker tested in free air.
(3) From T/S parameters, measured with LMS DA LPM module.
(4) The Xmax is calculated as: (Hvc - Hg)/2+ Hg/4. Hvc is the voice coil height and Hg the gap height.
(5) The Xmech is calculated as: (Hvc - Hg)/2 +(Hg-2). Hvc is the voice coil height and Hg the gap height.
(6) Thiele-Small parameters are measured after preconditioning: a) at 20°C- 22°C, 50% humidity for 2 hours; b) by LMS LSI measurement.