4″ / 119 mm
Nominal diameter
68 Hz
Resonance
0.41
Q factor
85 dB
Sensitivity
± 3 mm
Linear excursion
300 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
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Parts Express
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Specifications
Sensitivity (1w, 1m, infinite baffle)
SPL1W
85.4
dB
Thiele & Small parameters
Resonance frequency (free air)
fS
68.0
Hz
Mechanical quality factor
QMS
3.03
Electrical quality factor
QES
0.48
Total quality factor
QTS
0.41
Large signal parameters
Maximum linear excursion
xmax
3.0
mm
Air volume displaced at xmax
VD
17
cm³
Power handling
P
150
W
Program power
Pmax
300
W
Voice Coil
Nominal impedance
Z
8
Ω
DC resistance
RE
5.4
Ω
Inductance (1kHz)
LE
0.36
mH
VC Diameter
54
mm
Winding height
HVC
12
mm
Winding material
Hexatech™ Aluminum
Magnet
Flux density
B
0.88
T
Force factor
Bl
5.4
N/A
Motor constant
Bl/√RE
2.32
N/√W
Air gap height
HAG
6
mm
Diaphragm
Effective diameter
85
mm
Effective area
SD
57
cm²
Moving mass
MMS
6.6
g
Moving mass (without air load)
MMD
6.2
g
Material
Damped polymer composite
Suspensions
Stiffness
KMS
1.14
N/mm
Compliance
CMS
880
µm/N
Equivalent volume to the compliance
VAS
3.5
L
Mechanical resistance
RMS
0.86
N·s/m
Dimensions
Nominal diameter
4
″
119
mm
Overall diameter
119
mm
Baffle cutout diameter
94
mm
Overall depth
56
mm
Flange thickness
5
mm
Mounting depth
51
mm
Volume occupied by the driver (estimated)
0.16
L
Net weight
0.518
kg
Similar speaker drivers to Morel EM 428
4″Woofer
fS
65 Hz
SD
50 cm²
65 - 15000 Hz
QTS
0.46
xmax
1.6 mm
SPL1W
85 dB
Bl/√RE
2.23
Pmax
50 W
4″Mid Bass
fS
63 Hz
SD
50 cm²
QTS
0.42
xmax
5.0 mm
SPL1W
85 dB
Bl/√RE
2.17
Pmax
60 W
4.5″
fS
65 Hz
SD
54 cm²
65 - 4000 Hz
QTS
0.46
xmax
3.0 mm
SPL1W
85 dB
Bl/√RE
2.4
Pmax
100 W