The group carried out their vocal overdubs during the afternoon of 18 October. Over the instrumental break and the outro, the harmonies consist of McCartney singing a third above and Lennon a tenth below Harrison's double-tracked lead vocal. During the same session, Ringo Starr added a tambourine part. Although some Beatles authors credit Martin as having played harmonium, Fontenot says this contribution is inaudible on the completed track. Jackson writes that the sound on "If I Needed Someone" was "so transcendent", in its combination of elements from the two Byrds songs and the Beatles' "soaring harmonies" and treble-rich guitar parts, that Lennon chose to use it for his "Rubber Soul" track "Nowhere Man". A mono mix of the song was made on 25 October, and a stereo mix on 26 October – the day the Beatles collected their MBEs from Buckingham Palace.