Seventh Sojourn contains the Moody Blues' hardest-rocking body of songs, and shows the sudden emergence of John Lodge, who had never been a writing mainstay of the band before, as a major songwriter with "Isn't Life Strange" and "I'm Just a Singer (In a Rock and Roll Band)" (which reflected some of the strain of the group members), both of which became hits. Lodge and Graeme Edge's driving rhythm section comes through, as does the improved keyboard device called the Chamberlain, which supplanted the Mellotron here with a much stronger sound (especially on-stage). Justin Hayward's "New Horizons" was the most romantic number since "Nights in White Satin."