Eighteen Sound 8NMB420 8Ω
Woofer
8″ / 200 mm
Nominal diameter
61 Hz
Resonance
0.28
Q factor
96 dB
Sensitivity
± 5.8 mm
Linear excursion
400 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
96.0
dB
Frequency response
60 - 5500
Hz
Thiele & Small parameters
Resonance frequency (free air)
fS
61.0
Hz
Mechanical quality factor
QMS
4.00
Electrical quality factor
QES
0.31
Total quality factor
QTS
0.28
Large signal parameters
Maximum linear excursion
xmax
5.8
mm
Air volume displaced at xmax
VD
133
cm³
Power handling
P
280
W
Program power
Pmax
400
W
Voice Coil
Nominal impedance
Z
8
Ω
DC resistance
RE
5.0
Ω
Inductance (1kHz)
LE
0.35
mH
VC Diameter
51
mm
Magnet
Force factor
Bl
10.0
N/A
Motor constant
Bl/√RE
4.47
N/√W
Diaphragm
Effective diameter
171
mm
Effective area
SD
230
cm²
Moving mass
MMS
14.9
g
Moving mass (without air load)
MMD
12.4
g
Suspensions
Stiffness
KMS
2.19
N/mm
Compliance
CMS
457
µm/N
Equivalent volume to the compliance
VAS
33
L
Mechanical resistance
RMS
1.43
N·s/m
Dimensions
Nominal diameter
8
″
200
mm
Overall diameter
210
mm
Baffle cutout diameter
186
mm
Overall depth
99
mm
Flange thickness
14
mm
Mounting depth
85
mm
Volume occupied by the driver (estimated)
0.72
L
Net weight
1.7
kg
Similar woofers to Eighteen Sound 8NMB420 8Ω
10″Woofer
fS
58 Hz
SD
346 cm²
60 - 5000 Hz
QTS
0.27
xmax
4.4 mm
SPL1W
95 dB
Bl/√RE
6.88
Pmax
700 W
10″Woofer
fS
61 Hz
SD
320 cm²
60 - 4000 Hz
QTS
0.31
xmax
4.0 mm
SPL1W
96 dB
Bl/√RE
6.45
Pmax
400 W
10″Coaxial
fS
65 Hz
SD
347 cm²
65 - 20000 Hz
QTS
0.28
xmax
7.4 mm
SPL1W
97 dB
Bl/√RE
6.73
Pmax
500 W