4″ / 100 mm
Nominal diameter
65 Hz
Resonance
0.46
Q factor
85 dB
Sensitivity
± 1.55 mm
Linear excursion
50 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
84.8
dB
Frequency response
65 - 15000
Hz
Thiele & Small parameters
Resonance frequency (free air)
fS
65.0
Hz
Mechanical quality factor
QMS
8.78
Electrical quality factor
QES
0.49
Total quality factor
QTS
0.46
Large signal parameters
Maximum linear excursion
xmax
1.55
mm
Air volume displaced at xmax
VD
7.8
cm³
Power handling
P
20
W
Program power
Pmax
50
W
Voice Coil
Nominal impedance
Z
8
Ω
DC resistance
RE
7.2
Ω
Inductance (1kHz)
LE
0.48
mH
VC Diameter
30
mm
Magnet
Force factor
Bl
5.98
N/A
Motor constant
Bl/√RE
2.23
N/√W
Weight
0.5
kg
Diaphragm
Effective diameter
80
mm
Effective area
SD
50
cm²
Moving mass
MMS
6
g
Moving mass (without air load)
MMD
5.7
g
Suspensions
Stiffness
KMS
1.0
N/mm
Compliance
CMS
1005
µm/N
Equivalent volume to the compliance
VAS
3.6
L
Mechanical resistance
RMS
0.28
N·s/m
Dimensions
Nominal diameter
4
″
100
mm
Overall diameter
128
mm
Baffle cutout diameter
105
mm
Overall depth
74
mm
Volume occupied by the driver (estimated)
0.44
L
Net weight
1.7
kg
Similar woofers to Fostex FW108HS
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
4″Mid-range
fS
68 Hz
SD
57 cm²
QTS
0.41
xmax
3.0 mm
SPL1W
85 dB
Bl/√RE
2.32
Pmax
300 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