The CymaScope is a commercial instrument that images sound on a shallow water membrane. This video runs the first twelve notes of a concert grand tuned to A4 = 440 Hz through it, capturing attack, sustain and decay for each, and the footage is genuinely good: pause it and you can see the geometry evolve as the string's partials arrive and reflect around the instrument.
The description's physical account is reasonable as far as it goes. A piano note is not a constant sound, its harmonic content changes over the note's life, and a water membrane responds to that. It is fair to say the pattern is a record of the sound interacting with this particular cell.
Where care is needed is the wider claim culture around such instruments — that a note has an intrinsic hidden shape, or that these images reveal something about health or consciousness. There is no evidence for that. What you are seeing is one water cell's modal response, which would look different in a cell of another size or depth. Watch it for the imaging, not for the metaphysics.