Hard rock Styx helped further cement heavy rock in the Midwest as a form of stadium rock. In 1978, Van Halen emerged from the Los Angeles music scene with a sound based around the skills of lead guitarist Eddie Van Halen. He popularised a guitar-playing technique of two-handed hammer-ons and pull-offs called tapping, showcased on the song "Eruption" from the album "Van Halen", which was highly influential in re-establishing hard rock as a popular genre after the punk and disco explosion, while also redefining and elevating the role of electric guitar. The opening years of the 1980s saw a number of changes
Hard rock III" (1970) and "Led Zeppelin IV" (1971). The latter included the track "Stairway to Heaven", which would become the most played song in the history of album-oriented radio. Deep Purple continued to define hard rock, particularly with their album "Machine Head" (1972), which included the tracks "Highway Star" and "Smoke on the Water". In 1975 guitarist Ritchie Blackmore left, going on to form Rainbow and after the break-up of the band the next year, vocalist David Coverdale formed Whitesnake. 1970 saw the Who release "Live at Leeds", often seen as the archetypal hard rock live album, and the following year