Fi Car Audio Alpha 12 S4

• Sensitivity (1W, 1m, infinite baffle) SPL1W 85.8dB

Thiele & Small parameters

• Resonance frequency (free air) fS 32.4Hz
• Mechanical quality factor QMS 7.17
• Electrical quality factor QES 0.61
• Total quality factor QTS 0.56

Large signal parameters

• Maximum linear excursion xmax 17mm
• Air volume displaced at xmax VD 816cm³
• Power handling P 600W
• Program power Pmax 1200W

Voice Coil

• Nominal impedance Z 4Ω
• DC resistance RE 3.1Ω
• Inductance (1kHz, estimated) LE 2.19mH

Magnet

• Force factor Bl 13.6N/A
• Motor constant Bl/√RE 7.74N/√W

Diaphragm

• Effective diameter 247mm
• Effective area SD 480cm²
• Moving mass MMS 181g
• Moving mass (without air load) MMD 173g

Suspensions

• Stiffness KMS 7.39N/mm
• Compliance CMS 135µm/N
• Equivalent volume to the compliance VAS 43.7L
• Mechanical resistance RMS 5.14N·s/m

Dimensions

• Nominal diameter 12″
• 305mm
• Volume occupied by the driver (estimated) 2.4L