Deep Purple never sounded more feral and forceful than on this 1972 live album, showcasing the best songs of their heavy Mark II lineup. The band were ramped up to play their songs harder and faster than in the studio (particularly the blazing “Child In Time”), and they created space for Ritchie Blackmore and Jon Lord to embark on a series of intense, dizzying musical duels (“Highway Star,” “Lazy”), with the guitar blazing out of the left speaker and the organ from the right.