"Itchycoo Park" is a psychedelic pop song written by Steve Marriott and Ronnie Lane, first recorded by their group, the Small Faces. The song reached number three in the UK Singles Chart in 1967.

"Itchycoo Park" was released by The Small Faces in August 1967. Together with "Lazy Sunday", "Tin Soldier" and "All or Nothing", the song is one of the band's biggest hits and has become a classic of its time.

The song reached number 16 in the American Billboard Hot 100 chart in 1968.

Long running British music magazine NME cites readers poll voting "Itchycoo Park" number 62 out of the top 100 singles of all time.

"Itchycoo Park" climbed the charts again when it was re-released on 13 December 1975.

The song was one of the first pop singles to use flanging, an effect that can be heard in the bridge section after each chorus. Most sources credit the use of the effect to Olympic Studios engineer George Chkiantz who showed it to the Small Faces regular engineer Glyn Johns; he in turn demonstrated it to the group, who were always on the lookout for innovative production sounds, and they readily agreed to its use on the single.

Although many devices were soon created that could produce the same effect by purely electronic means, the effect as used on "Itchycoo Park" was at that time an electro-mechanical studio process. Two synchronised tape copies of a finished recording were played simultaneously into a third master recorder, and by manually retarding the rotation of one of the two tape reels (flanges) using the fingers, a skilled engineer could subtly manipulate the phase difference between the two sources, creating the lush 'swooshing' phase effect that sweeps up and down the frequency range. Because the original single version was mixed and mastered in mono, the flanging effect in "Itchycoo Park" is more pronounced in its original mono mix, and is noticeably diluted in the subsequent stereo mix.

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