Celestion CF1540HD

• Sensitivity (1W, 1m, infinite baffle) SPL1W 94.9dB
• Frequency response 35 - 2000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 40.8Hz
• Mechanical quality factor QMS 5.59
• Electrical quality factor QES 0.32
• Total quality factor QTS 0.31

Large signal parameters

• Maximum linear excursion xmax 10.5mm
• Air volume displaced at xmax VD 898cm³
• Power handling P 1200W
• Program power Pmax 2400W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.2Ω
• Inductance (1kHz) LE 1.22mH
• VC Diameter 100mm
• Winding height HVC 25mm
• Winding material Round copper
• Former material Glass fibre

Magnet

• Force factor Bl 24.4N/A
• Motor constant Bl/√RE 10.8N/√W
• Air gap height HAG 8mm
• Weight 3.18kg
• Material Ferrite

Diaphragm

• Effective diameter 330mm
• Effective area SD 855cm²
• Moving mass MMS 146g
• Moving mass (without air load) MMD 128g
• Material Glass loaded paper (weather-resistant)

Suspensions

• Stiffness KMS 9.09N/mm
• Compliance CMS 110µm/N
• Equivalent volume to the compliance VAS 108L
• Mechanical resistance RMS 6.67N·s/m
• Surround material Cloth-sealed

Dimensions

• Nominal diameter 15″
• 381mm
• Overall diameter 393mm
• Baffle cutout diameter 354mm
• Overall depth 184mm
• Volume occupied by the driver (estimated) 5.4L
• Net weight 11.2kg
• Frame material Cast aluminium