SB Acoustics SB20PFCS30-7

• Sensitivity (1W, 1m, infinite baffle) SPL1W 88.2dB

Thiele & Small parameters

• Resonance frequency (free air) fS 39Hz
• Mechanical quality factor QMS 4.50
• Electrical quality factor QES 0.77
• Total quality factor QTS 0.66

Large signal parameters

• Maximum linear excursion xmax 5.5mm
• Air volume displaced at xmax VD 122cm³
• Power handling P 40W
• Program power Pmax 80W

Voice Coil

• Nominal impedance Z 7Ω
• DC resistance RE 5.0Ω
• Inductance (1kHz) LE 0.95mH
• VC Diameter 30.5mm
• Winding height HVC 16mm

Magnet

• Flux density B 0.91T
• Force factor Bl 5.6N/A
• Motor constant Bl/√RE 2.5N/√W
• Air gap height HAG 5mm
• Weight 0.36kg

Diaphragm

• Effective diameter 168mm
• Effective area SD 222cm²
• Moving mass MMS 19.6g
• Moving mass (without air load) MMD 17.2g
• Material Natural fibers (made in-house)

Suspensions

• Stiffness KMS 1.18N/mm
• Compliance CMS 850µm/N
• Equivalent volume to the compliance VAS 59.5L
• Mechanical resistance RMS 1.07N·s/m
• Surround material Foam

Dimensions

• Nominal diameter 8″
• 203mm
• Volume occupied by the driver (estimated) 0.38L
• Net weight 0.96kg
• Frame material Reinforced plastic