2.5″ / 64 mm
Nominal diameter
90 Hz
Resonance
0.61
Q factor
79 dB
Sensitivity
± 3.5 mm
Linear excursion
30 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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Specifications
Sensitivity (1w, 1m, infinite baffle)
SPL1W
78.6
dB
Frequency response
85 - 20000
Hz
Thiele & Small parameters
Resonance frequency (free air)
fS
89.5
Hz
Mechanical quality factor
QMS
5.56
Electrical quality factor
QES
0.68
Total quality factor
QTS
0.61
Large signal parameters
Maximum linear excursion
xmax
3.5
mm
Air volume displaced at xmax
VD
5.5
cm³
Power handling
P
15
W
Program power
Pmax
30
W
Voice Coil
Nominal impedance
Z
4
Ω
DC resistance
RE
3.5
Ω
Inductance (1kHz)
LE
0.44
mH
VC Diameter
19
mm
Former material
Kapton® / Polyimide
Magnet
Force factor
Bl
2.68
N/A
Motor constant
Bl/√RE
1.43
N/√W
Diaphragm
Effective diameter
45
mm
Effective area
SD
16
cm²
Moving mass
MMS
2.5
g
Moving mass (without air load)
MMD
2.5
g
Material
Black Anodized Aluminum
Suspensions
Stiffness
KMS
0.79
N/mm
Compliance
CMS
1260
µm/N
Equivalent volume to the compliance
VAS
0.53
L
Mechanical resistance
RMS
0.25
N·s/m
Dimensions
Nominal diameter
2.5
″
64
mm
Overall diameter
64
mm
Baffle cutout diameter
52
mm
Overall depth
48
mm
Volume occupied by the driver (estimated)
0.15
L
Similar speaker drivers to Dayton Audio ND65-4
2″Full-range
fS
93 Hz
SD
15 cm²
QTS
0.61
xmax
2.0 mm
SPL1W
80 dB
Bl/√RE
1.25
Pmax
20 W
2.5″Woofer
fS
94 Hz
SD
22 cm²
80 - 5000 Hz
QTS
0.55
xmax
4.3 mm
SPL1W
81 dB
Bl/√RE
1.84
Pmax
20 W
2.5″Full-range
fS
109 Hz
SD
17 cm²
200 - 20000 Hz
QTS
0.51
xmax
4.3 mm
SPL1W
82 dB
Bl/√RE
1.46
Pmax
12 W