Beethoven's listening tube

From the age of 30 Beethoven became increasingly deaf. Twelve years later, Johann Nepomuk Mälzel, who also invented the metronome, made these ear trumpets for him. When Beethoven was not even 50 years old, even these did not help anymore and Beethoven could only talk with a conversation booklet. The more deaf he became, the less he could fulfil his obligations as a conductor and pianist. In the end, the only thing left for him was composing.