What you would hear if the M2 had a microphone

[jwt873]

I was curious to see what it would sound like if the the Mavic 2 drone came with a microphone.

In order to obtain the sound of the drone, I mounted an 808 Keychain camera on top, just above the gimbal. This camera records both video and audio. https://www.amazon.com/808-Keychain-Camera-HD-Products/dp/B019EJ78NE

I used Velcro to attach the camera to the M2. The thick fiber side of the velcro (that the little hooks fasten to) did a good job of isolating the camera from the shell of the drone.

I started the M2 up and took off with both the 808 camera and the Mavic camera recording. While post processing, I stripped the sound from the 808 Keychain camera video and then synced it up with the video recorded by the Mavic 2.

Below is an image showing where the camera was mounted on the drone, and the final video with the synced motor sounds.

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[old man mavic]

I was curious to see what it would sound like if the the Mavic 2 drone came with a microphone.

In order to obtain the sound of the drone, I mounted an 808 Keychain camera on top, just above the gimbal. This camera records both video and audio. https://www.amazon.com/808-Keychain-Camera-HD-Products/dp/B019EJ78NE

I used Velcro to attach the camera to the M2. The thick fiber side of the velcro (that the little hooks fasten to) did a good job of isolating the camera from the shell of the drone.

I started the M2 up and took off with both the 808 camera and the Mavic camera recording. While post processing, I stripped the sound from the 808 Keychain camera video and then synced it up with the video recorded by the Mavic 2.

Below is an image showing where the camera was mounted on the drone, and the final video with the synced motor sounds.

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View attachment 65055

the go pro type camera i had mounted on my early x21 drone sounded very similar to that, it was all right for a while listening on play back ,but then i used to turn off the sound as it became annoying after so long the only good part was listening to the conversations, between my friend and i when we were flying ,before take off and then on landing

 

[FormerMember07122019_2]

I was hoping for an AH-HA moment but all you get is motor and wind noise so all I get is a DUH moment.

 

[zocalo]

Yeah, about what I was expecting. A steady "hum" that probably aligns with the rpm of the rotors and maybe some harmonics, plus a bit of ambient wind noise in the background.

I've wondered about maybe suspending a microphone under the drone though, with maybe a metre or two of cable to reduce the rotor noise - you could then potentially use a bandpass filter to filter out the rest in post and get a reasonably clean soundtrack. You'd need to be careful on takeoff/landing to avoid the cable snarling in the rotors, but a sufficiently weighty mic should be enough to keep it clear once in flight.

Not really something I'd use, but could be interesting for some videographers out there who specifically want to capture local audio where they can't get without a drone. Some kinds of wildlife or hazardous geological locations, like the various fire pits where coal/gas/oil has ignited underground, perhaps?

 

[Porky]

On startup, that sounded like a Dji Inspire.

 

[kilomikebravo]

I was curious to see what it would sound like if the the Mavic 2 drone came with a microphone.

JW: I am regularly amazed at the ideas some folks have and this one is no exception. TOO COOL to actually hear the girl in flight! Thanks for that, amigo.

 

[Sniperfritz]

Bzzzz

 

[sar104]

Anyone who flew the earlier models in the Phantom range with a GoPro is well accustomed to that sound.

 

[Aussie Oldtimer]

i wonder what you really expected to hear considering that you can hear them at 50 plus m agl.

 

[altaic]

Since the harmonics of the M2 are predictable, I wonder what it’d sound like if you filtered them out. And put a big wind muffler thing over the mic. Seems doable.

 

[Elude]

I love it. Makes me feel like I’m on a small prop plane.

 

[zocalo]

Since the harmonics of the M2 are predictable, I wonder what it’d sound like if you filtered them out. And put a big wind muffler thing over the mic. Seems doable.

I think so too, but the rotor speed varies, so the frequency of the sound will as well which might make it fiddly unless you are OK with just blanking out the entire frequency range(s) where rotor noise is present.

It *should* be a fairly clear spike (or set of spikes) on the audio though, and they should have a much higher amplitude than any ambient, so it might not be too hard to write a bandpass filter that just looks for such spikes and squelches them regardless of the frequency. Any harmonics might be a little harder to detect as they'll have lower amplitudes but it's still better than nothing, and you could maybe use the min/max rpm of the rotors as a guide as well. Boost the gain on what's left and you should have some useable audio, I would think.

 

[jwt873]

Since the harmonics of the M2 are predictable, I wonder what it’d sound like if you filtered them out. And put a big wind muffler thing over the mic. Seems doable.

One thing that could be done would be to use two microphones. One in contact with the frame and the other one hanging free and isolated from the drone, pointed away from the motors.

The frame mounted mic would pick up only the drone sounds while the outside mic would pick up the sound of the drone as well as ambient sounds.

Then you could take the output of the frame mounted microphone and mix the signal 180 degrees out of phase with the outside microphone. This would cancel out the drone noise, while leaving the ambient sounds intact.

 

[jwt873]

Anyone who flew the earlier models in the Phantom range with a GoPro is well accustomed to that sound.

Yes.. About 7 years ago, I used that little 808 Keychain camera on a $100 toy drone. That was my first foray into aerial photography.

After that I flew a GoPro equipped hexacopter before moving to the Phantom and then to the Mavic... That's what made me think of recording the sound. Many modern flyers have never heard it.