The band started their second US tour in April 1969 with little support from their almost-bankrupt American label and without an album to promote, because of a delay in the manufacturing of the new LP. During the tour, Deep Purple showed a remarkable progress as performers and a musical direction more oriented towards a heavier and louder sound than before. Doubts about the compatibility of vocalist Rod Evans with the hard rock music that other band members wanted to pursue brought about the decision to search for a substitute, which was found in Ian Gillan of the band Episode Six. Gillan had formed a songwriting duo with Episode Six's bassist Roger Glover, who was also invited to join Deep Purple and replace Nick Simper. The band's new line-up, identified as Mark II, debuted live in London on 10 July 1969.