Eminence EJ-1240

• Sensitivity (1W, 1m, infinite baffle) SPL1W 100.8dB
• Frequency response 80 - 5000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 75Hz
• Mechanical quality factor QMS 20.09
• Electrical quality factor QES 0.54
• Total quality factor QTS 0.53

Large signal parameters

• Maximum linear excursion xmax 1.2mm
• Air volume displaced at xmax VD 64cm³
• Power handling P 40W
• Program power Pmax 80W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 7.0Ω
• Inductance (1kHz) LE 0.6mH
• VC Diameter 44mm
• Winding material Copper
• Former material Paper

Magnet

• Force factor Bl 12.1N/A
• Motor constant Bl/√RE 4.57N/√W
• Air gap height HAG 8mm
• Weight 0.992kg
• Material Alnico

Diaphragm

• Effective diameter 257mm
• Effective area SD 520cm²
• Moving mass MMS 24g
• Moving mass (without air load) MMD 15.6g
• Material Paper

Suspensions

• Stiffness KMS 5.26N/mm
• Compliance CMS 190µm/N
• Equivalent volume to the compliance VAS 71.2L
• Mechanical resistance RMS 0.56N·s/m
• Surround material Paper

Dimensions

• Nominal diameter 12″
• 305mm
• Overall diameter 309mm
• Baffle cutout diameter 283mm
• Overall depth 159mm
• Volume occupied by the driver 2.24L
• Net weight 3.81kg
• Frame material Pressed steel