Fi Car Audio BTL4 18 D2
2x1Ω
2x2Ω
Subwoofer
18″ / 470 mm
Nominal diameter
25 Hz
Resonance
0.52
Q factor
88 dB
Sensitivity
± 33 mm
Linear excursion
7000 W
Program Power
- Sensitivity (1W, 1m, infinite baffle)
- SPL1W
- 88.1
- dB
- Resonance frequency (free air)
- fS
- 25.0
- Hz
- Mechanical quality factor
- QMS
- 7.59
- Electrical quality factor
- QES
- 0.55
- Total quality factor
- QTS
- 0.52
- Maximum linear excursion
- xmax
- 33.0
- mm
- Air volume displaced at xmax
- VD
- 3993
- cm³
- Power handling
- P
- 3500
- W
- Program power
- Pmax
- 7000
- W
- Nominal impedance
- Z
- 2 x 2
- Ω
- DC resistance (in series)
- RE
- 2.8
- Ω
- Inductance (1kHz, in series, estimated)
- LE
- 1.85
- mH
- Force factor (in series)
- Bl
- 20.2
- N/A
- Motor constant
- Bl/√RE
- 12.1
- N/√W
- Effective diameter
- 393
- mm
- Effective area
- SD
- 1210
- cm²
- Moving mass
- MMS
- 554
- g
- Moving mass (without air load)
- MMD
- 524.2
- g
- Stiffness
- KMS
- 13.7
- N/mm
- Compliance
- CMS
- 73
- µm/N
- Equivalent volume to the compliance
- VAS
- 151
- L
- Mechanical resistance
- RMS
- 11.47
- N·s/m
- Nominal diameter
- 18
- ″
- 470
- mm
- Overall diameter
- 470
- mm
- Baffle cutout diameter
- 425
- mm
- Mounting depth
- 241
- mm
- Volume occupied by the driver
- 2.83
- L