Fi Car Audio SP4 12 D2

• Sensitivity (1W, 1m, infinite baffle) SPL1W 83.4dB

Thiele & Small parameters

• Resonance frequency (free air) fS 27.9Hz
• Mechanical quality factor QMS 6.01
• Electrical quality factor QES 0.47
• Total quality factor QTS 0.44

Large signal parameters

• Maximum linear excursion xmax 33mm
• Air volume displaced at xmax VD 1584cm³
• Power handling P 3000W
• Program power Pmax 6000W

Voice Coil

• Nominal impedance Z 2 x 2Ω
• DC resistance (in series) RE 2.5Ω
• Inductance (1kHz, in series, estimated) LE 2.92mH

Magnet

• Force factor (in series) Bl 19.1N/A
• Motor constant Bl/√RE 12N/√W

Diaphragm

• Effective diameter 247mm
• Effective area SD 480cm²
• Moving mass MMS 376g
• Moving mass (without air load) MMD 368g

Suspensions

• Stiffness KMS 11.8N/mm
• Compliance CMS 84.5µm/N
• Equivalent volume to the compliance VAS 27.4L
• Mechanical resistance RMS 11N·s/m

Dimensions

• Nominal diameter 12″
• 318mm
• Overall diameter 318mm
• Baffle cutout diameter 283mm
• Mounting depth 286mm
• Volume occupied by the driver 5.38L