DC resistance Rdc 3,4 Ω Nominal impedance ZN 4 Ω Resonance frequency fs 720 HZ Voice coil diameter 28 mm SPL 2,83V/1m 93 dB Dome/Kalotte Fine cloth silk Cut-off Frequency / Trennfrequenz > 2200 Hz 12 dB/Oct > 1500 Hz 18 dB/Oct