Celestion TF1520

• Sensitivity (1W, 1m, infinite baffle) SPL1W 96dB
• Frequency response 45 - 4000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 54.9Hz
• Mechanical quality factor QMS 5.17
• Electrical quality factor QES 0.84
• Total quality factor QTS 0.72

Large signal parameters

• Maximum linear excursion xmax 3mm
• Air volume displaced at xmax VD 257cm³
• Power handling P 150W
• Program power Pmax 300W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.8Ω
• Inductance (1kHz) LE 0.8mH
• VC Diameter 50mm
• Winding height HVC 14.5mm
• Winding material Round copper
• Former material Polyimide

Magnet

• Force factor Bl 12.5N/A
• Motor constant Bl/√RE 5.19N/√W
• Air gap height HAG 8mm
• Weight 1.1kg
• Material Ferrite

Diaphragm

• Effective diameter 330mm
• Effective area SD 855cm²
• Moving mass MMS 65.5g
• Moving mass (without air load) MMD 48.2g
• Material Kevlar loaded paper

Suspensions

• Stiffness KMS 7.69N/mm
• Compliance CMS 130µm/N
• Equivalent volume to the compliance VAS 133L
• Mechanical resistance RMS 4.37N·s/m
• Surround material Cloth-sealed

Dimensions

• Nominal diameter 15″
• 381mm
• Overall diameter 385mm
• Baffle cutout diameter 352mm
• Overall depth 158mm
• Volume occupied by the driver (estimated) 2.9L
• Net weight 5.0kg
• Frame material Pressed steel