21″ / 530 mm
Nominal diameter
31 Hz
Resonance
0.28
Q factor
97 dB
Sensitivity
± 10.5 mm
Linear excursion
2000 W
Program Power
Driver
Port
Combined
Frequency response
Hz
Impedance
Ω
Impedance Phase
°
Excursion
mm
Velocity
m/s
SPL
dB
Acoustical Phase
°
Group Delay
ms
Transient response
ms
Sensitivity (1w, 1m, infinite baffle)
SPL1W
96.5
dB
Frequency response
30 - 1000
Hz
Thiele & Small parameters
Resonance frequency (free air)
fS
31.4
Hz
Mechanical quality factor
QMS
18.30
Electrical quality factor
QES
0.28
Total quality factor
QTS
0.28
Large signal parameters
Maximum linear excursion
xmax
10.5
mm
Air volume displaced at xmax
VD
1783
cm³
Power handling
P
1000
W
Program power
Pmax
2000
W
Voice Coil
Nominal impedance
Z
8
Ω
DC resistance
RE
5.4
Ω
Inductance (1kHz)
LE
1.9
mH
VC Diameter
152
mm
Winding height
HVC
30
mm
Former material
Glass Fibre
Magnet
Flux density
B
1.1
T
Force factor
Bl
35.86
N/A
Motor constant
Bl/√RE
15.5
N/√W
Air gap height
HAG
15
mm
Diaphragm
Effective diameter
465
mm
Effective area
SD
1698
cm²
Moving mass
MMS
342.9
g
Moving mass (without air load)
MMD
293.8
g
Suspensions
Stiffness
KMS
13.39
N/mm
Compliance
CMS
75
µm/N
Equivalent volume to the compliance
VAS
303
L
Mechanical resistance
RMS
3.7
N·s/m
Dimensions
Nominal diameter
21
″
530
mm
Overall diameter
550
mm
Baffle cutout diameter
492
mm
Overall depth
218
mm
Flange thickness
14
mm
Mounting depth
204
mm
Volume occupied by the driver (estimated)
9.5
L
Net weight
16.3
kg
Similar subwoofers to Precision Devices PDN.2151
18″Low frequency
fS
33 Hz
SD
1164 cm²
30 - 2000 Hz
QTS
0.28
xmax
6.0 mm
SPL1W
97 dB
Bl/√RE
9.76
Pmax
1200 W
18″Woofer
fS
30 Hz
SD
1180 cm²
30 - 2500 Hz
QTS
0.27
xmax
5.0 mm
SPL1W
96 dB
Bl/√RE
11
Pmax
1000 W
18″Subwoofer
fS
32 Hz
SD
1213 cm²
35 - 2500 Hz
QTS
0.30
xmax
11.3 mm
SPL1W
96 dB
Bl/√RE
11
Pmax
1400 W