Fostex W400A-HR

• Sensitivity (1W, 1m, infinite baffle) SPL1W 92.8dB
• Frequency response 25 - 2500Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 25Hz
• Mechanical quality factor QMS 8.20
• Electrical quality factor QES 0.32
• Total quality factor QTS 0.31

Large signal parameters

• Maximum linear excursion xmax 5.5mm
• Air volume displaced at xmax VD 451cm³
• Power handling P 67W
• Program power Pmax 200W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 6.0Ω
• Inductance (1kHz) LE 2.64mH
• VC Diameter 100mm

Magnet

• Force factor Bl 19.5N/A
• Motor constant Bl/√RE 7.96N/√W
• Weight 3.1kg
• Material Alnico

Diaphragm

• Effective diameter 323mm
• Effective area SD 820cm²
• Moving mass MMS 130g
• Moving mass (without air load) MMD 113g

Suspensions

• Stiffness KMS 3.03N/mm
• Compliance CMS 330µm/N
• Equivalent volume to the compliance VAS 310L
• Mechanical resistance RMS 2.49N·s/m

Dimensions

• Nominal diameter 15″
• 400mm
• Overall diameter 395mm
• Baffle cutout diameter 357mm
• Overall depth 242mm
• Volume occupied by the driver (estimated) 9.8L
• Net weight 21.4kg