Earlier tonight, something started playing in my head. It was this:
That's the the first movement (allegro assai) of Beethoven's Piano Sonata No. 23 in F minor, popularly known as the Appassionata sonata. This particular recording was done on a period instrument, a reconstruction of a type of piano that Beethoven would have actually been able to play. I like this recording because the sound is distinctly different from that of a piano from today, and you can tell that the construction of the instrument is not as hardy as that of modern models. Go back and listen closely to the selection at about the 38-39 second mark.
There you will hear something that I have never heard on a modern piano: string clatter. The performer is playing the forte parts with such power that the strings vibrate massively, interfering with each other before their sounds fade. You can hear string clatter sometimes on a vigorously strummed guitar with slack strings, but I have never heard piano wires do this before I heard this recording. It's a testament to the power of Beethoven's works and the level of performance he demanded from musicians and instruments.
One can imagine piano makers after Beethoven working hard to make their instruments more sturdy.