In ear headphones series sennheiser cx line sennheiser classic line type of fitting in ear transmission mode wired features gold plated jacks sound function passive noise reduction sound mode stereo sensitivity 113 dbmw impedance 16 ohm frequency response 19 21000 hz number of drivers 1 distortion factor 02 length of cable 12 m types of cable ofc asymmetrical double sided jack 35 mm jack shape l shaped colour black earcup colour bla