Possible Clues:

• Tim's 'Aida' collaborator
• Lyrical John
• ..... Jonn (musician)
• Rocker ___ John
• First name in rock since 1970
• John with an outrageous wardrobe
• Let on he's John, the singer
• The Continental fashion suits British singer
• Country yodeler ___ Britt
• 'Silly Cow' playwright Ben