SB ACOUSTICS SB12PFCR25-4-COAX, 12cm FIBER CONE COAX with 12mm SOFT DOME 4OHMFeatures Vented reinforced plastic chassis Proprietary cone material with natural fibers made in-house Soft low damping rubber surround for improved transient response Optimized motor system Non-resonant long life lead wires Compact large surround dome tweeter SpecsSPECS WOOFER: Nominal Impedance 4 Ω DC resistance, Re 3.1 Ω Voice coil inductance, Le 0.26 mH Effective piston area, Sd 45 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 1.0 T Magnet weight 0.40 kg Net weight 0.86 kg Free air resonance, Fs 58 Hz Sensitivity (2.83V/1m) 87 dB Mechanical Q-factor, Qms 4.07 Electrical Q-factor, Qes 0.36 Total Q-factor, Qts 0.33 Moving mass incl. air,Mms 4.5 g Force factor, Bl 3.8 Tm Equivalent volume, Vas 4.8 liters Compliance, Cms 1.66 mm/N Mechanical loss, Rms 0.4 kg/s Rated power handling* 30 W * IEC 268-5, T/S parameters measured on drive units that are broken in. SPECS TWEETER: Nominal Impedance 4 Ω DC resistance, Re 3.0 Ω Voice coil diameter 12.4 mm Voice coil height 1.2 mm Air gap height 1.5 mm Free air resonance, Fs 1300 Hz Sensitivity (2.83V/1m) 89 dB Rated power handling* 10 W Magnetic flux density 1.05 T Magnet weight 0.003 kg Net weight 0.014 kg
