Paul's voice cracks a little during "will go".
At the tail end of the guitar sound, sounds like a long slide down the frets (a sort of "purrrr" sound).
Click, slightly left of centre.
Click, right channel, as guitar ends.
Bass guitar mishap.
In OOPS only, the vocal leakage goes "gets in, stops stops my mind". Somewhere over to the left there is leakage of a previous/guide vocal, where the phrasing was different, because the double-track lead doesn't cause this.
Faint maracas on right, before they join in proper at 0:31.
George can be heard tapping along in time, between guitar passages ("Knock-a knock-a ...").
Introduced with John saying "Queen says 'No' to pot smoking FBI members". It is curious, in that this was edited in here deliberately.
A faint guide vocal can be heard to the left on "hope you feel it too", slightly ahead of the beat.
Reports indicate that in the horn solo, a possible punch-in occurs. A glitch in the sustained tone before the final flourish gives it away. However, it has been strongly suggested that this was a playing technique of the hornist, as it also happens in the Give My Regards To Broadstreet version.
It is further observed by Ugo Coppola, that
In The Complete Beatles Chronicle, Lewisohn says that the hornist, Alan Civil , recorded the whole solo eight times, wiping over the tape with every try. No punch-ins or edits.
Chris Chardi adds
The noise you hear in the middle of the french horn solo may be due to a technique called "circular breathing." It is used by brass and woodwind players so that they can play long lines more fluidly without having to stop and take a giant breath. Given the peerless fluidity of Alan Civil's solo, I think it's very likely that this is what happened.
Reported as "track volume goes down a notch", I can only assume this is because the bass guitar sound becomes thinner. It loses the low-end punch from here, just slightly, all the way to the end of the track.
Ringo's kick drum pedal squeaks (left channel in stereo versions). Obvious around 0:50-0:55 and 1:32-1:34 in mono version.
John sings "So call on me", Paul sings "Just call on me".
1:43 to end
Bad edit, this is only in the Capitol "Beatles 1962-1966" album. The harmonica goes out of time, and the vocals suddenly double track (left channel).
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