What do the black stripes in headphone pins mean?

Question

Some headphone pins have only one stripe, some have two, my ipod earphones have three? What do they actually mean? Is it related to the quality of output? Thanks.

Answer 1

They separate positive and negative polaritys for the speakers..

Ipod speakers have 3 because the function of the ipod out jack is multi faceted, basically for example a shuffle gets charged and synced through the headphone jack so the signals nedd to be split up to their relative connecting plates internally..good querstion!

Answer 2

The black bit is an insulator.  If it has one stripe them there will be 2 electrical connections, 2 stripes would give 3 and 3 stripes would give 4.  Some jacks have more connections so that the device can be remote controlled by an inline remote.