by donizetti. his lyric tenor voice, coupled with an impeccable technique, means he is master of the high note. singing they used to be called 'the money notes'. - you had to sing those high cs, and if you didn't, the _ whole performance was ruined. juan diego's status as one of the world's leading tenors has earned him great admiration. and he comes to the stage at the royal opera house to give masterclasses to aspiring opera stars. singing