"Hey Jude" is amongst my favourite Beatles songs. I do not know when I first heard it but I certainly remember a colleague of mine at the Civil Aviation Radio Measurements Station, Pailton, near Rugby, Warwick, England, Britain, The World, The Solar System, The Local Galaxy, The Universe in the signal generator laboratory, a man of Welsh descent who had a famous brother, a TV producer who worked for the BBC, singing it non-stop for days on end whilst calibrating his signal generators. Jup! The Beatles have a lot to answer for! Such is the power of "Hey Jude" that it never became boring.
The eleven-times "Da" plus "hey, Jude" as a coda and chorus, is for me the very essence of Beatles music. Although actually very short, the listener has the feeling that the song goes on for ever.
The version that I play can be found in Beatles Songs for the Recorder