Before revision: 250px|Five-pin male 180° DIN connector from a 1988 Schneider MF2 keyboard by Cherry The DIN connector is an electrical connector that was standardized by the (DIN), the German Institute for Standards, in the mid 1950's, initial with 3 pins for mono, but when stereo connections and gear appeared in late 1950's ( 1959 or so), versions with 5 pins or more were launched.
After revision: 250px|Five-pin male 180° DIN connector from a 1988 Schneider MF2 keyboard by Cherry The DIN connector is an electrical connector that was standardized by the (DIN), the German Institute for Standards, in the mid 1950's, initially with 3 pins for mono, but when stereo connections and gear appeared in late 1950's ( 1959 or so), versions with 5 pins or more were launched.