Sgt. Pepper's Lonely Hearts Club Band "Being for the Benefit of Mr. Kite!" and "A Day in the Life". Producer George Martin and engineer Geoff Emerick helped realise the group's ideas by approaching the studio as an instrument, applying orchestral overdubs, sound effects and other methods of tape manipulation. Recording was completed on 21 April 1967. The cover, depicting the Beatles posing in front of a tableau of celebrities and historical figures, was designed by the British pop artists Peter Blake and Jann Haworth. "Sgt. Pepper" is regarded by musicologists as an early concept album that advanced the use of extended form in popular music while
Sgt. Pepper's Lonely Hearts Club Band the Beatles' "Rubber Soul" album. McCartney said he was highly impressed with the songs' "harmonic structures" and the choice of instruments used in Wilson's musical arrangements, and that these elements encouraged him to think the Beatles could "get further out" than the Beach Boys had. He added: "we were inspired by it and nicked a few ideas." According to author Kenneth Womack, the Beach Boys' subsequent release, the "Good Vibrations" single, was viewed by the Beatles and Martin as "a direct challenge" to their supremacy. McCartney identified "Pet Sounds" as his main musical inspiration for "Sgt. Pepper", although he said