Celestion TF1225e

• Sensitivity (1W, 1m, infinite baffle) SPL1W 95.3dB
• Frequency response 50 - 3000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 52.6Hz
• Mechanical quality factor QMS 3.51
• Electrical quality factor QES 0.37
• Total quality factor QTS 0.33

Large signal parameters

• Maximum linear excursion xmax 5.3mm
• Air volume displaced at xmax VD 279cm³
• Power handling P 300W
• Program power Pmax 600W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 6.4Ω
• Inductance (1kHz) LE 1.32mH
• VC Diameter 64mm
• Winding height HVC 14.5mm
• Winding material Edgewound copper
• Former material Polyimide

Magnet

• Force factor Bl 17.7N/A
• Motor constant Bl/√RE 6.97N/√W
• Air gap height HAG 8mm
• Weight 1.4kg
• Material Ferrite

Diaphragm

• Effective diameter 260mm
• Effective area SD 531cm²
• Moving mass MMS 54g
• Moving mass (without air load) MMD 45.4g
• Material Kevlar loaded paper

Suspensions

• Stiffness KMS 5.88N/mm
• Compliance CMS 170µm/N
• Equivalent volume to the compliance VAS 67.7L
• Mechanical resistance RMS 5.08N·s/m
• Surround material Cloth-sealed

Dimensions

• Nominal diameter 12″
• 305mm
• Overall diameter 309mm
• Baffle cutout diameter 283mm
• Overall depth 139mm
• Volume occupied by the driver (estimated) 2.1L
• Net weight 4.4kg
• Frame material Pressed steel