Beethoven is the Classical composer that, arguably, produced better compositions after the onset of his deafness. Whenever one thinks about a classical composer that went deaf, you think of Beethoven. There is a story that one time after one of his concerts (while he was deaf), since he couldn't hear, and since he was conducting, he thought that the audience hated the piece so he didn't even turn around. Finally, one of the musicians went and turned him to show him an audience gushing with tears.