21NDS151U4 Subwoofers 21 inchs

Notes

- 6 INCH COPPER VOICE COIL 

96.5 dB/SPL SENSITIVITY

-4400 WATT PROGRAM POWER HANDING

FEM OPTIMIZED MOTOR AND SUSPENSIONS

- 51.5mm PEAK TO PEAK MAXIMUM EXCURSION

OPTIMIZED COOLING SYSTEM

DOUBLE SPIDER

RESONANCE FREE AND HEAVY DUTY BASKET DESIGN

TRIPLE ROLL SURROUND

GENERAL SPECIFICATIONS

Nominal diameter 545(21) mm (in.)
Nominal impedance 8 Ω
Minimum impedance 7.7 Ω
Program power (1) 4400 W
AES Power rating(2) 2200 W
Sensitivity (3) 96.5 dB
Frequency range 29~1000 Hz
Voice coil diameter 151(6) mm (in.)
Chassis material Aluminium
Magnet material Neodymium
Magnet dimensions (ODxIDxh) 146x60x10 mm
Coil material SV
Former material Glass Fiber
Xmax(4) 16.5 mm
Xmech(5) 25.7 mm
Gap height 15 mm
Voice coil Winding height 40.5 mm

SMALL SIGNAL PARAMETERS

DC resistance(Re) 6 Ω
Resonance frequency(Fs) 28.9 Hz
Moving mass(Mms) 438 g
Compliance(Cms) 0.07 mm/N
Force factor(BL) 32.3 N/A
Mechanical Q-factor(Qms) 5.8
Electrical Q-factor(Qes) 0.37
Total Q-factor(Qts) 0.35
Equivalent air volume(Vas) 353 I
Voice coil Inductance(Le) 2.98 mH
Diaphragm area(Sd) 1750 cm2
Reference efficiency(Eta O) 2.4 %

SHIPPING INFORMATION

Net weight 21.4 Kg
Multipack size (1) (W x D x H) 570x570x290 mm
Multipack weight 242 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.