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0 pointsdoix2y ago0 comments

Wikipedia is actually a pretty good source for this [0]. tl;dr it's not as simple as one drone makes X noise, so 2 drones make 2x noise. For that to happen, the drones need to be making noise at the same frequency and be perfectly in phase. Also, if they were perfectly out of phase, they could cancel the noise from each other out (this is how noise cancelling headphones work).

[0] https://en.wikipedia.org/wiki/Wave_interference

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amelius2y ago· 1 in thread

That's a long article. My intuition says that if a sound source produces a number of Watts per square meter, then those numbers should add up.

In fact that's what it says here:

https://personalpages.manchester.ac.uk/staff/richard.baker/B...

Of course assuming uncorrelated noise, as a crude approximation.

jacquesm2y ago

Yes, but it isn't uncorrelated noise. That's the whole problem here. Long articles are long for a reason, in this case that this is a complex issue. And prop noise is an ideal candidate for such interference.

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