Celestion FTX1530

• Sensitivity (1W, 1m, infinite baffle) SPL1W 98dB
• Frequency response 40 - 18000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 42.5Hz
• Mechanical quality factor QMS 3.81
• Electrical quality factor QES 0.30
• Total quality factor QTS 0.28

Large signal parameters

• Maximum linear excursion xmax 6mm
• Air volume displaced at xmax VD 513cm³
• Power handling P 400W
• Program power Pmax 800W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.4Ω
• Inductance (1kHz) LE 0.82mH
• VC Diameter 75mm
• Winding height HVC 16mm
• Winding material Edgewound copper clad aluminium
• Former material Glass fibre

Magnet

• Force factor Bl 20.2N/A
• Motor constant Bl/√RE 8.71N/√W
• Air gap height HAG 8mm
• Weight 2.3kg
• Material Ferrite

Diaphragm

• Effective diameter 330mm
• Effective area SD 855cm²
• Moving mass MMS 84.3g
• Moving mass (without air load) MMD 66.9g
• Material Kevlar loaded paper

Suspensions

• Stiffness KMS 5.88N/mm
• Compliance CMS 170µm/N
• Equivalent volume to the compliance VAS 172L
• Mechanical resistance RMS 5.91N·s/m
• Surround material Cloth-sealed

Dimensions

• Nominal diameter 15″
• 381mm
• Overall diameter 387mm
• Baffle cutout diameter 351mm
• Overall depth 176mm
• Volume occupied by the driver (estimated) 4.6L
• Net weight 9.1kg
• Frame material Cast aluminium