Fi Car Audio SP4 12v2+ D2

• Sensitivity (1W, 1m, infinite baffle) SPL1W 85dB

Thiele & Small parameters

• Resonance frequency (free air) fS 27.9Hz
• Mechanical quality factor QMS 7.96
• Electrical quality factor QES 0.30
• Total quality factor QTS 0.29

Large signal parameters

• Maximum linear excursion xmax 33mm
• Air volume displaced at xmax VD 1584cm³
• Power handling P 3500W
• Program power Pmax 7000W

Voice Coil

• Nominal impedance Z 2 x 2Ω
• DC resistance (in series) RE 2.5Ω
• Inductance (1kHz, in series, estimated) LE 2.97mH

Magnet

• Force factor (in series) Bl 24N/A
• Motor constant Bl/√RE 15.1N/√W

Diaphragm

• Effective diameter 247mm
• Effective area SD 480cm²
• Moving mass MMS 386g
• Moving mass (without air load) MMD 378g

Suspensions

• Stiffness KMS 11.6N/mm
• Compliance CMS 86µm/N
• Equivalent volume to the compliance VAS 27.1L
• Mechanical resistance RMS 8.5N·s/m

Dimensions

• Nominal diameter 12″
• 318mm
• Overall diameter 318mm
• Baffle cutout diameter 283mm
• Mounting depth 254mm
• Volume occupied by the driver 5.38L