The Scan-speak D2905/9300 is a 1" textile dome tweeter with a very flat frequency response and low distortion. The D2905/9300 achieves a lower resonance and increased clarity by using several coatings of damping material on the dome and chambering behind the dome. Both these damping factors and the use of a light magnetic fluid, reduce the resonances as much as possible, while reducing compression affects. this tweeters linear response and openness make it a good choice for any system. TECHNICAL DATA: Sensitivity 2.83V/1M 90dB  Free air resonance Fs 650 Hz DC resistance 4.7 ohm V.C. inductance 0.08 mH Power 12dB@Hz 150W@2.5K Effective cone area 8.5 cm2 V.C. diameter 28 mm V.C. height - Air gap height - Lin. & max. excursion ±0.4 / ±1.5 mm Air gap flux density - Force factor BL Product 3.5 Tm Moving mass incl. air 0.45 g Net weight 0.7 kg Outside diameter: 104.5mm Cut out: 74mm Depth: 41mm 25.4mm = 1" = 2.54cm