The Beatles' unfolding innovation in the recording studio reaches its apex with the album's final track. Lennon's "Tomorrow Never Knows" was one of the first songs in the emerging genre of psychedelic music, and included such groundbreaking techniques as reverse guitar, processed vocals and looped tape effects. Musically, it is drone-like, with a strongly syncopated, repetitive drum-beat. The lyrics were inspired by Timothy Leary's book, The Psychedelic Experience: A Manual Based on the Tibetan Book of the Dead, although the title itself was inspired by a Ringo Starr malapropism.Although George Harrison had used the sitar before "Within You Without You," it was this track on The Beatles' masterpiece, Sgt. Pepper's Lonely Hearts Club Band that deserves credit for introducing the sitar and Eastern mysticism into the popular culture.
Much of the backing track consists of a series of prepared tape loops, stemming from Lennon's and McCartney's interest in and experiments with magnetic tape and musique concrète techniques at that time. According to The Beatles' session chronicler Mark Lewisohn, Lennon and McCartney prepared a series of loops at home, and these then were added to the pre-recorded backing track. This was reportedly done live in a single take, with multiple tape recorders running simultaneously, some of the longer loops extending out of the control room and down the corridor.
Lennon's processed lead vocal was another innovation. Always in search of ways to enhance or alter the sound of his voice, he gave a directive to EMI engineer Geoff Emerick that he wanted to sound like he was singing from the top of a high mountain. Emerick solved the problem by routing a signal from the recording console into the studio's Leslie speaker, giving Lennon's vocal its ethereal, filtered quality (he was later reprimanded by the studio's management for doing this).
A key production technique used for the first time on this album was automatic double tracking (ADT), invented by EMI engineer Ken Townsend on 6 April 1966. This technique used two linked tape recorders to automatically create a doubled vocal track. The standard method was to double the vocal by singing the same piece twice onto a multitrack tape, a task Lennon particularly disliked. The Beatles were reportedly delighted with the invention, and used it extensively on Revolver. ADT quickly became a standard pop production technique, and led to related developments, including the artificial chorus effect.
"Within You Without You" features only Harrison and a group of uncredited Indian musicians, and was written on a harmonium at the house of long-time Beatles' friend Klaus Voormann, while "there were lots of joints being smoked".And here is that mashup, a perfect mystical Beatles mashup if there ever was one...
The song, originally written as a 30-minute piece and trimmed down into a mini-version for the album, is in Locrian mode. The laughter at the end was Harrison's idea to lighten the mood and follow the theme of the album.
The song was also included on the 2006 remix album Love. For this album, George Harrison's lyrics and melody were mixed over the rhythm of "Tomorrow Never Knows," although the opening lyric, "Turn off your mind... Relax... And float downstream........ It is not dying.......... It is not dying." came from "Tomorrow Never Knows," as does the set of reversed sound effects utilized in the mashup. The blending of these two songs is considered the most effective form of mashup on the album.
Stephen Stills was so impressed by the lyrics that he had them carved on a stone monument in his yard. John Lennon pronounced it "one of George's best songs."