Material
Cone: Paper
Spider: Nomex
Surround: Rubber
Coil former: Fibreglass
Basket: Aluminum
Dust Cap: Fiberglass

Specifications
DC resistance (Rdc): 3,2 Ω
Nominal impedance (ZN): 4 Ω
Resonance frequency (fs): 26,3 Hz
Voice coil diameter: 2,5 inch
Mechanical Q factor (Qms): 6,03
Electrical Q factor (Qes): 0,43
Total Q factor (Qts): 0,4
Moving mass (Mms): 143,8 g
Effective piston area (Sd): 490 cm²
Mechanical resistance (Rms): 3,9 kg/s
Compliance (Cms): 0,26 mm/N
Force factor (BL): 12,8 Tm
Equivalent air volume (Vas): 105,5 dm³
SPL 2,83V/1m: 91,3 dB