Which mega-famous guitarist/singer was born John Asher? Clue; I've seen him on stage.

There seems to be conflicting evidence as to this, so, as I can't delete the question, let me clear it up. Jack Bruce started out using the pseudonym "John Asher" for a short while, but several sources say that the 'Asher' bit was actually only one of his given names and that his full given names were John Symon Asher (Bruce). OK, next question.