Fostex FE103En

• Sensitivity (1W, 1m, infinite baffle) SPL1W 91.3dB
• Frequency response 83 - 22000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 83Hz
• Mechanical quality factor QMS 2.75
• Electrical quality factor QES 0.38
• Total quality factor QTS 0.33

Large signal parameters

• Maximum linear excursion xmax 0.6mm
• Air volume displaced at xmax VD 3cm³
• Power handling P 5W
• Program power Pmax 15W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 7.5Ω
• Inductance (1kHz) LE 0.04mH
• VC Diameter 20mm

Magnet

• Force factor Bl 4.99N/A
• Motor constant Bl/√RE 1.82N/√W
• Weight 0.193kg
• Material Ferrite

Diaphragm

• Effective diameter 80mm
• Effective area SD 50cm²
• Moving mass MMS 2.55g
• Moving mass (without air load) MMD 2.3g

Suspensions

• Stiffness KMS 0.606N/mm
• Compliance CMS 1650µm/N
• Equivalent volume to the compliance VAS 5.95L
• Mechanical resistance RMS 0.48N·s/m

Dimensions

• Nominal diameter 4″
• 100mm
• Overall diameter 107mm
• Baffle cutout diameter 93mm
• Overall depth 46mm
• Volume occupied by the driver (estimated) 0.14L
• Net weight 0.58kg