Fountek FR58EX

• Sensitivity (1W, 1m, infinite baffle) SPL1W 82.1dB
• Frequency response 130 - 20000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 134Hz
• Mechanical quality factor QMS 2.60
• Electrical quality factor QES 0.69
• Total quality factor QTS 0.55

Large signal parameters

• Maximum linear excursion xmax 2.9mm
• Air volume displaced at xmax VD 5cm³
• Power handling P 15W
• Program power Pmax 30W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 6.4Ω
• Inductance (1kHz, estimated) LE 0.22mH
• VC Diameter 20mm
• Winding height HVC 8.9mm
• Winding material Copper
• Former material Aluminum

Magnet

• Flux density B 1.16T
• Force factor Bl 3.89N/A
• Motor constant Bl/√RE 1.54N/√W
• Air gap height HAG 3mm
• Material Neodymium

Diaphragm

• Effective diameter 47mm
• Effective area SD 17.4cm²
• Moving mass MMS 1.91g
• Moving mass (without air load) MMD 1.9g

Suspensions

• Stiffness KMS 1.36N/mm
• Compliance CMS 737µm/N
• Equivalent volume to the compliance VAS 0.315L
• Mechanical resistance RMS 0.62N·s/m

Dimensions

• Nominal diameter 2.5″
• 58mm
• Overall diameter 62mm
• Overall depth 35mm
• Net weight 0.14kg