Medieval music was just the notes, leaving all expression to the director and performers, but over the centuries, writer and musicians specified voice on the page more. Musicians leave more markings, as do playwrights. Edward Albee was compulsive about how folks were to say lines, so his stage directions are a catalogue of subtly different voices:
"From a distance; curiously lighter, higher voice"; "oddly loud, tough" "a bit as if to a child" "dismissive laugh" "shakes her head in admiration" "tiny pause" "small smug triumph" "dogged, but not unpleasant"; "purrs" "weary"; "longer pause, none too pleasant"; "unconcerned". (77) (MacFarquhar, Larissa. "Passion Plays: The Making of Edward Albee." The New Yorker (4 April 2005): 68-77.)