Soundboard upload

a hundredths comparator is required. The evaluation is quite complex.

which piano is it? how old is it?

before resorting to this measurement, other examinations of the instrument can be taken into consideration.

There is this piano that has very annoying vibrations on the sixth octave. I checked the height of the strings on the bridge, to see if there was some object fallen inside causing them, and I wanted to understand if the problem lies in the crown of the soundboard or if you have something else to suggest. I am attaching a video and photos

I can't see the photos... anyway. Try this: press down on the bridge while playing. If the vibration disappears, it could depend on even a minimal detachment of the bridge. Also try applying pressure under the soundboard in correspondence with the strings.

Great advice, thank you