SB ACOUSTICS SB29BAC-C000-4, 29mm BERYLLIUM DOME TWEETERFeatures Beryllium dome for non-resonant high frequency extension Large surround dome for increased acoustic output Copper cap for reduced voice coil inductance and minimum phase shift Saturation controlled motor system for low distortion Dual balanced compression chambers for improved dynamics Flow optimized vented pole piece for optimum coupling to rear chamber Non-reflective rear chamber with optimized damping for improved dynamics CCAW voice coil for low moving mass Long life flexible lead wires Cast aluminium faceplate Low resonance frequency Specs Nominal Impedance 4 Ω DC resistance, Re 3.0 Ω Voice coil inductance, Le 0.05 mH Effective piston area, Sd 9.6 cm2 Voice coil diameter 29.0 mm Voice coil height 2.0 mm Air gap height 2.5 mm Linear coil travel (p-p) 0.5 mm Moving mass incl. air, Mms 0.46 g Free air resonance, Fs 650 Hz Sensitivity (2.83V/1m) 93 dB Mechanical Q-factor, Qms 2.71 Electrical Q-factor, Qes 1.22 Total Q-factor, Qts 0.84 Force factor, Bl 2.4 Tm Rated power handling* 80 W Magnetic flux density 1.1 T Magnet weight 0.22 g Net weight 0.5 kg * IEC 268-5, high-pass Butterworth, 2600 Hz, 12 dB/oct