Fostex FE203Σ-RE

• Sensitivity (1W, 1m, infinite baffle) SPL1W 96.5dB
• Frequency response 54 - 18000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 54Hz
• Mechanical quality factor QMS 8.51
• Electrical quality factor QES 0.23
• Total quality factor QTS 0.23

Large signal parameters

• Power handling P 9W
• Program power Pmax 18W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 7.2Ω
• Inductance (1kHz) LE 0.29mH
• VC Diameter 35mm

Magnet

• Force factor Bl 12.1N/A
• Motor constant Bl/√RE 4.51N/√W
• Weight 1.16kg

Diaphragm

• Effective diameter 162mm
• Effective area SD 206cm²
• Moving mass MMS 14g
• Moving mass (without air load) MMD 11.8g

Suspensions

• Stiffness KMS 1.59N/mm
• Compliance CMS 630µm/N
• Equivalent volume to the compliance VAS 37.8L
• Mechanical resistance RMS 0.56N·s/m

Dimensions

• Nominal diameter 8″
• 200mm
• Overall diameter 208mm
• Baffle cutout diameter 185mm
• Volume occupied by the driver (estimated) 1.7L
• Net weight 4.08kg