I also like how unrealistic the "drumheads" proposed in the proof were: https://en.wikipedia.org/wiki/Hearing_the_shape_of_a_drum
Sounded different than a normal drum. Was pink sparkle coated, so perhaps that had something to do with it :)
The drum kit is still in the shop to this day (crazy old guy wants far too much for anything in the shop, as it has been there for an eternity, and well, all old is expensive, right?) I think about that set every now and then, as I myself was interested at one time.
I heard about this problem from David Webb (one of the people who found that the answer was no) back when I was a grad student at Dartmouth College.
You can’t hear the shape of a drum. But can you hear the shape of a cowbell?
It’s really too bad that PBS canceled infinite series.