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As an aside, the ring can be recorded and then used to discover damaged parts. If it sounds wrong, it is damaged.

https://www.youtube.com/watch?v=pOWwx7nAPvk&t=45s shows wind turbine bolts evaluated in that same way. (Mind the NN voiceover.)

Does this work with human bodies?

I'll take a wild guess and say that's how ultrasound diagnostics work