Penacova is a municipality in the Coimbra region of Portugal. The Mondego River flows through the valley, to Coimbra, and eventually to the estuary at Figueira da Foz, on the Atlantic coast.
We compared the Mavic Mini, Mavic Pro, and Mavic 2 loudness levels using a sound level meter on an iPad, and some unscientific methods. We crashed the Mavic pro into a tree too. Conclusion: They all have similar sound levels, but the Master Airscrew props really blended in with the background noise, as they seemed to have a lower frequency. Maybe human ears aren't as perceptive at the lower frequencies, or there is too much other noise (wind, city noises, etc) at the lower frequencies.
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https://www.youtube.com/watch?v=miVV-JzTohE