Headband headphones nominal impedance 32 ohm 35 mm stereo jack plug cable length 14 m series sennheiser px line sennheiser classic line type of fitting on ear transmission mode wired features collapsible sensitivity 115 dbmw impedance 32 ohm frequency response 10 21000 hz distortion factor 01 length of cable 14 m jack 35 mm weight 60 g