Material
Cone: PFP
Surround: Rubber
Basket: Aluminum
Spider: Nomex
Coil former: Aluminium
Dust Cap: Paper

Specifications
Power: Pe 500/750 RMS/Nom
DC resistance: Rdc 3,7 Ω
Nominal impedance: ZN 4 Ω
Resonance frequency: fs 27 Hz
Voice coil diameter: 2,5 inch
X-Max: +/- 12,5 mm
Mechanical Q factor: Qms 6,32
Electrical Q factor: Qes 0,40
Total Q factor: Qts 0,38
Moving mass: md 135 g
Effective piston area: Sd 510 cm2
Mechanical resistance: Rms 3,95 kg/s
Compliance: Cms 0,26 mm/N
Force factor: BL 13,95 Tm
Equivalent air volume: Vas 93,72 Liter
SPL 2,83V/1m: 92 dB
External diameter: 312 mm / 12,28 inch
Installation diameter: 283 mm / 11,14 inch
Installation depth: 152 mm / 5,98 inch
Magnet diameter: 155 mm / 6,10 inch