“All You Need Is Love” contains an asymmetric time signature and complex changes. Musicologist Russell Reising writes that, although the song represents the peak of the Beatles’ overtly psychedelic phase, the change in metre during the verses is the sole example of the experimental aspect that typifies the band’s work in that genre.The main verse pattern contains a total of 29 beats, split into two 7
4 measures, a single bar of 8
4, followed by a one bar return of 7
4 before repeating the pattern. The chorus, however, maintains a steady 4
4 beat with the exception of the last bar of 6
4 (on the lyric “love is all you need”). The prominent cello line draws attention to this departure from pop-single normality, although it was not the first time that the Beatles had experimented with varied metre within a single song: “Love You To” and “She Said She Said” were earlier examples.

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