"Good Day Sunshine" is a song by The Beatles on the 1966 album Revolver. It was written by Paul McCartney, with help from John Lennon, and credited to Lennon/McCartney. Leonard Bernstein praised the song for its construction in a 1967 CBS News documentary. Richie Unterberger of allmusic said the song "radiates optimism and good vibes" and Ian MacDonald said it is "superbly sung by McCartney and exquisitely produced by George Martin and his team" and "displays The Beatles at their effortless best."
The song was recorded at Abbey Road 8 June 1966, with overdubs added the following day. McCartney sang the lead vocal and also played bass guitar and piano accompanied by Ringo Starr on drums. Music critic Ian MacDonald was unsure if John Lennon played guitar on the track; in his description of the recording sessions for the song, Mark Lewisohn did not mention a guitar track. Lennon and George Harrison add harmony vocals during the choruses. Lennon can be barely heard repeating "she feels good" after McCartney at 1:27. George Martin played the piano solo, recorded with the tape recorder running slower than usual and thus in the released version the solo sounds faster than it was actually...