Lynne Cahill recently presented longitudinal research on the vowels of Sir Mick Jagger at English Melodies/PAC International Conference, run by the Laboratoire Parole et Langage in Aix-En-Provence. The study was jointly conducted with a final year undergraduate student, Kate Jellyman, and was a development of her exciting undergraduate final year project.
Lynne and Kate tracked three of Sir Mick's vowels between 1964 and 2013. For comparison, the vowels of speakers of Received Pronunciation and 'cockney' were also examined for a similar time-frame. Lynne and Kate used Praat software to analyse the relevant vowel sounds, and found that, overall, Jagger's vowels are somewhat closer to 'cockney' (but this is not always consistent), and that, in general, his vowels have stayed the same over time.
Who said that linguists aren't rock-and-roll?