Kraftwerk are a German electronic music band formed by Ralf Hütter and Florian Schneider in 1970 in Düsseldorf. The band was fronted by both Hütter and Schneider until Schneider's departure in 2008. The signature Kraftwerk sound combines driving, repetitive rhythms with catchy melodies, mainly following a Western classical style of harmony, with a minimalistic and strictly electronic instrumentation. The group's simplified lyrics are at times sung through a vocoder or generated by computer-speech software. Kraftwerk was one of the first groups to popularize electronic music and are considered to be pioneers.