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"Tomorrow Never Knows" is a song by the English rock band the Beatles, written primarily by John Lennon and credited to Lennon–McCartney. It was released in August 1966 as the final track on their album Revolver, although it was the first song recorded for the LP. The song marked a radical departure for the Beatles, as the band fully embraced the potential of the recording studio without consideration for reproducing the results in concert. [Wikipedia]
Lennon adapted the lyric from Timothy Leary's The Psychedelic Experience, itself a Westernised reading of the Bardo Thödol (the 'Tibetan Book of the Dead'). The title — 'tomorrow never knows' — was taken from a Ringo malapropism, a phrase the drummer had used in passing. John Lennon's closing vision 'Tomorrow Never Knows,' based on the Tibetan Book of the Dead, ranks among the most experimental and prescient recordings the Beatles produced. The song's disorienting vocal processing, tape-loop accompaniment, and sitar and tabla integration created a psychedelic soundscape that anticipated electronic music and drone traditions. Lennon's lead vocal, processed through a Leslie speaker cabinet to create otherworldly effect, delivered philosophical abstraction with hypnotic precision (Lewisohn 1988, p.70). Kozinn positions both 'Tomorrow Never Knows' and 'She Said She Said' as vivid psychedelic narratives rich in LSD-influenced imagery, representing the album's sophisticated engagement with drug experimentation and surrealist lyrical composition. (Kozinn 1995, p.146,152)
Cut in a single afternoon on 6 April 1966 — the very first session of the Revolver project. The track is built on a single chord (C), Ringo playing a heavily-compressed loop-feel pattern, McCartney's bass providing the harmonic motion. Lennon's vocal was fed through a rotating Leslie speaker (taken from an organ cabinet) for the second half of the track — a Geoff Emerick experiment that violated EMI engineering protocols. Five tape loops, prepared on home Brennell machines, were fed in live to the mix from five different studios on EMI's three floors, each operated by a separate engineer with a finger on the spool to maintain pitch. Recorded across multiple sessions beginning the track employed extensive tape-loop techniques with pre-recorded fragments of sitar, tabla, and orchestral materials layered beneath Lennon's vocal. George Martin's pioneering use of ADT (Automatic Double Tracking) and Leslie speaker processing created the song's signature vocal character. Geoff Emerick's engineering mastered the technical challenges of layering and mixing disparate sound sources into coherent psychedelic composition (Lewisohn 1988, p.70).