Jensen Blackbird P 12/40 BB

• Sensitivity (1W, 1m, infinite baffle) SPL1W 96.6dB

Thiele & Small parameters

• Resonance frequency (free air) fS 93.2Hz
• Mechanical quality factor QMS 14.29
• Electrical quality factor QES 1.50
• Total quality factor QTS 1.36

Large signal parameters

• Power handling P 40W
• Program power Pmax 80W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.9Ω
• Inductance (1kHz) LE 0.4mH
• VC Diameter 32mm
• Winding height HVC 9mm
• Winding material Copper
• Former material Kapton

Magnet

• Flux density B 1.28T
• Force factor Bl 8.2N/A
• Motor constant Bl/√RE 3.38N/√W
• Air gap height HAG 6mm
• Weight 0.3kg
• Material Reinforced Alnico

Diaphragm

• Effective diameter 250mm
• Effective area SD 491cm²
• Moving mass MMS 28.7g
• Moving mass (without air load) MMD 20.8g
• Material Paper

Suspensions

• Stiffness KMS 9.8N/mm
• Compliance CMS 102µm/N
• Equivalent volume to the compliance VAS 34.6L
• Mechanical resistance RMS 1.18N·s/m
• Surround material Integrated Paper

Dimensions

• Nominal diameter 12″
• 307mm
• Overall diameter 307mm
• Volume occupied by the driver (estimated) 0.82L
• Net weight 2.0kg
• Frame material Pressed Sheet