Theodore "Teddy" Berg is "...one of the most famous living American composers..." and a character in the 1969 novel Real People by Alison Lurie. he's come to Illyria, a artists' retreat in New England. He's in a copyright case against a record company.
He thinks Ricky Potter is a brilliant young composer.
Teddy's fame is even greater, though less explicit. Everyone knows that he changed the course of modern music, but even here at Illyria probably no one but Ricky (and possibly Caroline) could tell you exactly how he did it.