Occasionally you stumble across reports of people capable of performing jaw-dropping feats. Take this guy, for example. Merely by examining the grooves on vinyl records he was able to deduce, with a very high level of accuracy, what the music was — assuming it was classical from the time of Beethoven or later.
I used to own about six vinyl versions of Bach’s Passacaglia and Fugue in C minor. I accumulated that many in pursuit of bass. The theme is largely carried on the pedals and ought to end one several of its cycles on the lowest C pedal. Depending on the design of the organ, this ought to be around 32 hertz and, in the case of organs with really big pipes, 16 hertz.
My collecting came to an end when I finally purchased a Telarc recording. This had a monster organ, 16 hertz fundamental, and a bone-chilling increase in volume towards the end of the Passacaglia. (It’s still available on CD.)
Notably, the modulation of the groove was clearly visible during the loud bits, with (from memory) excursions up to a millimetre or so! Of course, few LPs carried such deep, loud bass for the simple reason that it uses up so much disc surface. Records with such widely spaced grooves were necessarily short in duration.