Revolver (Beatles album) group collective since 1962, and gave them an unprecedented amount of time to prepare for a new album. Writing in "The Beatles Forever", Nicholas Schaffner cites 1966 as the start of the band's "'psychedelic' period" and adds: "That adjective implies not only the influence of certain mind-altering chemicals, but also the freewheeling spectrum of wide-ranging colors that their new music seemed to evoke." Music journalist Carol Clerk describes "Revolver" as having been "decisively informed by acid", following John Lennon and George Harrison's continued experimentation with the drug LSD since the spring of 1965.<ref name="Clerk/Uncut"> Available at Rock's Backpages (subscription required).</ref>
The Beatles (album) the Byrds. Edwin Faust of "Stylus Magazine" described "The Beatles" as "foremost an album about musical purity (as the album cover and title suggest). Whereas on prior Beatles albums, the band was getting into the habit of mixing several musical genres into a single song, on "The White Album" every song is faithful to its selected genre. The rock n' roll tracks are purely rock n' roll; the folk songs are purely folk; the surreal pop numbers are purely surreal pop; and the experimental piece is purely experimental." The only western instrument available to the group during their Indian visit