Deep Purple began life in England in 1968 as a progressive rock band. Universally regarded as trailblazers, alongside Led Zeppelin and Black Sabbath, the three bands were considered to be the "unholy trinity of British hard rock and heavy metal in the early to mid-Seventies". Embracing a change in direction toward hard rock in 1970, Deep Purple made the Guinness Book of World Records as "the globe's loudest band" for a 1972 concert at London's Rainbow Theatre. Having traversed several line-up changes throughout their career, and an eight-year hiatus (1976-1984), the band's most commercially successful period took place from 1969 - 1973. The band has sold over 100 million albums worldwide, including 8.5 million certified units in the US, and ranked number 22 on VH1's Greatest Artists of Hard Rock program, with a poll on British radio station Planet Rock ranking them 5th among the "most influential bands ever".