Celestion TN1225

• Sensitivity (1W, 1m, infinite baffle) SPL1W 97.8dB
• Frequency response 50 - 4000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 61.4Hz
• Mechanical quality factor QMS 3.12
• Electrical quality factor QES 0.34
• Total quality factor QTS 0.31

Large signal parameters

• Maximum linear excursion xmax 2.5mm
• Air volume displaced at xmax VD 133cm³
• Power handling P 250W
• Program power Pmax 500W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.2Ω
• Inductance (1kHz) LE 0.65mH
• VC Diameter 64mm
• Winding height HVC 13mm
• Winding material Round copper
• Former material Polyimide

Magnet

• Force factor Bl 15.8N/A
• Motor constant Bl/√RE 6.92N/√W
• Air gap height HAG 8mm
• Material Neodymium

Diaphragm

• Effective diameter 260mm
• Effective area SD 531cm²
• Moving mass MMS 42.1g
• Moving mass (without air load) MMD 33.5g
• Material Kevlar loaded paper

Suspensions

• Stiffness KMS 6.25N/mm
• Compliance CMS 160µm/N
• Equivalent volume to the compliance VAS 63.7L
• Mechanical resistance RMS 5.21N·s/m
• Surround material Cloth-sealed

Dimensions

• Nominal diameter 12″
• 305mm
• Overall diameter 309mm
• Baffle cutout diameter 283mm
• Overall depth 132mm
• Volume occupied by the driver (estimated) 1.2L
• Net weight 2.0kg
• Frame material Pressed steel