Sgt. Pepper's Lonely Hearts Club Band album carried on the childhood and Liverpool theme with its circus and fairground effects, its pervading atmosphere of the traditional northern music hall that was in both its main creators' [McCartney and Lennon's] blood." "Sgt. Pepper" album cover was designed by the pop artists Peter Blake and Jann Haworth. Blake recalled of the concept: "I offered the idea that if they had just played a concert in the park, the cover could be a photograph of the group just after the concert with the crowd who had just watched the concert, watching them. If we did this by using cardboard
Album era "A Christmas Gift for You from Phil Spector" (1963), the Beatles' "Rubber Soul" (1965), the Beach Boys' "Pet Sounds" (1966), the Mothers of Invention's "Freak Out!" (1966), and the Beatles' "Sgt. Pepper's Lonely Hearts Club Band" (1967). In reference to the Beatles' "Rubber Soul", "Revolver" (1966) and "Sgt. Pepper" and the Beach Boys' "Pet Sounds", writer Bill Martin noted: "In the wake of these albums, many rock musicians took up the 'complete album approach.'" "Rolling Stone" assistant editor Andy Greene felt that "Sgt. Pepper's" "was the beginning of the album era. It was the big bang of albums." According to