Fountek FR58C

• Sensitivity (1W, 1m, infinite baffle) SPL1W 83.1dB
• Frequency response 154 - 10000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 154Hz
• Mechanical quality factor QMS 2.37
• Electrical quality factor QES 2.39
• Total quality factor QTS 1.19

Large signal parameters

• Maximum linear excursion xmax 1.1mm
• Air volume displaced at xmax VD 2cm³
• Power handling P 5W
• Program power Pmax 10W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 6.4Ω
• Inductance (1kHz, estimated) LE 0.14mH
• VC Diameter 21.1mm
• Winding height HVC 5.2mm
• Winding material Copper Clad Aluminium
• Former material Kapton

Magnet

• Flux density B 0.7T
• Force factor Bl 1.61N/A
• Motor constant Bl/√RE 0.64N/√W
• Air gap height HAG 3mm
• Material Ferrite

Diaphragm

• Effective diameter 48mm
• Effective area SD 18.1cm²
• Moving mass MMS 1g
• Moving mass (without air load) MMD 0.9g

Suspensions

• Stiffness KMS 0.943N/mm
• Compliance CMS 1060µm/N
• Equivalent volume to the compliance VAS 0.493L
• Mechanical resistance RMS 0.41N·s/m

Dimensions

• Nominal diameter 2.5″
• 58mm
• Overall diameter 61mm
• Overall depth 39mm
• Net weight 0.213kg