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>
A Collection of Beatles Oldies Out" and "Paperback Writer", were remixed in stereo for the album, since the majority of the Beatles' singles had only been mixed for mono release previously. The stereo mixing was overseen by George Martin, the Beatles' producer, with none of the band members present. The mixing sessions took place between 31 October and 10 November 1966 at EMI Studios (later Abbey Road Studios) in London. Martin was surprised at how time-consuming the remixing of "She Loves You" and "I Want to Hold Your Hand" proved to be. In the case of "She Loves You", the 1963 two-track recording tape had