Twenty-three-year-old singer Gwyneth Herbet is the hottest young thing in UK jazz. “In only 18 months, Herbert has gone from trying to persuade landlords to turn off the telly and let her sing in their pubs, to rehearsing for the concert she’s giving at the Queen Elizabeth Hall to open the London Jazz Festival on Tuesday. Not long ago she was lucky if she could get someone with influence in the music world merely to agree to listen to her demo tape. Now she can count princes and pop legends among her admirers.”