@Laure, thank for your corrections of that translation. I was a bit in a hurry so it was kinda literal translation. Also, I was not sure about « placer la voix dans le masque », so I left the whole explanation as it was.
@Marc Placer la voix dans le masque is a set phrase that seems to be only used by singers and actors. I did not know it in French and had to look for it and I haven't got a clue whether a similar phrase exists in English, need someone involved with acting or singing to tell us.