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.