Harold Holzer, a Lincoln scholar, told CBS News: “Lincoln died long before audio recording was possible so we have no hints about what he really sounded like, except the reminiscences of his contemporaries. The most frequent things we read are that he had a nasal, high voice that somehow miraculously floated over large crowds.”Day-Lewis said "said the voice materialised 'in my mind’s ear'" and "If I hear a voice, I tend to believe that I hear it for good reason.”
Here's a new trailer, including some of Day-Lewis's vocalizations. I don't have a problem with the presumably historically grounded high-pitched voice. But what's the point of going realistic about the sound of Lincoln's voice when everything else about the movie seems all theatrical and pretentious, including the lines Day-Lewis must speak with that voice? "I am the President of the United States clothed with enormous power!"