[sniglom]

Sorry if hijacking,

I have a drone (DJI FPV) with a microphone. It can pick up some sounds, but the loudness from the rotors makes it really hard to hear in playback.

The rotor noise varies in frequency and has several harmonics as well, so it can't be band passed.

I understand that you can't get a clean or great signal from it, but something would be nice.

What tool would be good to use to filter out that noise?

[DanTremonti]

If you want to filter out the rotor noise alone, switching to a directional microphone would be the best option IMO.

[pwython]

Aside from the buzzing rotors, wouldn't wind noise be a big issue too? When recording your flights, what noises do you want it to pick up?