For the broadcast, The Beatles were (except for Ringo) seated on stools, accompanied by a small studio orchestra. They were surrounded by friends and acquaintances seated on the floor, many of whom were among the leading stars of the British pop scene, who sang with the refrain during the fade-out. The performance was not completely live: The Beatles, the orchestra, and guests were overdubbing onto a pre-recorded rhythm track mainly consisting of piano, harpsichord, drums, and backing vocals. The full Our World segment opens with the band and company listening to the raw backing track, as commentator Steve Race explained the process in voiceover. The live overdubs seem to include not only lead vocals, orchestra, and the improvised call-and-response, but also bass guitar, Harrison's guitar solo, and a second drum track — which seems to go out of time with the original track during the first few bars. At the beginning of the song, under "La Marseillaise," a tambourine is shaken, but this was mixed out and replaced with a drum roll before the single was released. Lennon, affecting indifference, was said to be nervous about the broadcast, given the potential size of the international TV audience. Dissatisfied with his singing, he re-recorded the solo verses for use on the single. Starr also overdubbed drums before the single was released, fixing the aforementioned timing problems and adding the drum roll. In the orchestral ending, you can hear pieces of both "Greensleeves," a Bach two-part invention (by George Martin) and Glen Miller's "In The Mood." Glen Miller's estate had to sue the Beatles over the use of "In the Mood", for backdated royalties. The song had never been cleared and properly credited.
Broadcast and also filmed in black and white only, the clip of the Beatles performing "All You Need Is Love" was expertly colourised from photos taken at the event, like the one at the top of this story. The production company kept the colourisation secret from the Beatles, and when George Harrison was shown the clip he didn't notice anything different about it. In his mind it had probably always been in colour. One, probably deliberate mistake, was made during the colourisation process: the Abbey Road studio chairs, used by the orchestra, had always, and still are, red. In the clip they were coloured blue.