But I needed to find out what the “Carnival of Light” really is. I browed around the web and learned that
this piece of Beatle’s music is termed as an experimental piece. And at 14 minutes is much much longer than “Hey Jude.”
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"Carnival of Light" was recorded on January 5, 1967. It was recorded after the vocal overdubbing sessions for "Penny Lane". Sir Paul McCartney has said it was around fifteen minutes but in “The Complete Beatles Chronicle” it's listed as lasting 13 minutes and 48 seconds.
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The song was recorded in January 1967, after designer David Vaughan painted a psychedelic design on a piano owned by Paul McCartney. David asked Paul if he could contribute a musical piece for the upcoming The Million Volt Light and Sound Rave, which was an art festival organised by Binder, Edwards & Vaughan. The Festival was a showcase for electronic music and light shows
And McCartney said yes.
According to Beatles expert Mark Lewisohn says the song included "distorted, hypnotic drum and organ sounds, a distorted lead guitar and the sound of a church organ.” Mark listened to the song in 1987 while compiling his book The Complete Beatles Recording Sessions, (published by Harmony Books) various effects (water gargling was one). He also says that Lennon and McCartney are also heard screaming and bawling aloud random phrases like 'Are you alright?'
Another buzz about Sir Paul is that he is “considering” writing the soundtrack for “Shrek 4.” I can imagine Donkey singing already.