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Couldn't you figure out the resonant frequency automatically by hitting the glass with a few impulses from the speaker and looking at the response? That'd be a fun signal processing exercise.

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I’m not a sound expert, but I’m curious how you think this would work?

When the glass starts resonating, it should start prouducing sound too, so you should be able to hear two frequencies as you get close to the right frequency — I think. (Not a sound expert either)

Applying fourier transform to impulse response results in the frequency response:

https://docs.scipy.org/doc/scipy/reference/generated/scipy.s...

I think this would work only if the system in question is reasonably linear though, which wine glass might not be (?)

Technically speaking, you don’t need to know the frequency response in detail, or whether it’s exactly linear. If the glass «sings» at a given frequency after being whacked by a short impulse, that’s a resonant frequency.

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