4″ SB12NRX25-4 / Norex
Features
- Proprietary cone material with natural fibres made in-house
- High damping Butyl rubber surround for non-resonant sound character
- Vented pole piece for reduced compression
- Vented cast aluminium chassis for optimum strength and low compression
- CCAW voice coil for reduced moving mass
- Long life silver lead wires
- Non-conducting fibre glass coil former for minimum damping
- Shorting ring in motor system for reduced distortion
Specs
- Nominal Impedance 4 Ω
- DC resistance, Re 3.1 Ω
- Voice coil inductance, Le 0.14 mH
- Effective piston area, Sd 50 cm2
- Voice coil diameter 25.4 mm
- Voice coil height 15 mm
- Air gap height 5 mm
- Linear coil travel (p-p) 10 mm
- Magnetic flux density 0.84 T
- Magnet weight 0.32 kg
- Net weight 0.76 kg
- Free air resonance, Fs 55 Hz
- Sensitivity (2.83 V / 1 m) 87.5 dB
- Mechanical Q-factor, Qms 3.2
- Electrical Q-factor, Qes 0.46
- Total Q-factor, Qts 0.40
- Moving mass incl. air, Mms 5.6 g
- Force factor, Bl 3.6 Tm
- Equivalent volume, VAS 5.6 liters
- Compliance, Cms 1.57 mm/N
- Mechanical loss, Rms 0.6 kg/s
- Rated power handling* 30 W
* IEC 268-5, T/S parameters measured on drive units that are broken in.