This might be harder to find at a thrift store than at an electronics or hobby store, but there are a large number of ultra-small toy helicopters on the market that can be had for not a lot of dosh. They’re flimsy. They don’t fly well. But they do scare the hell out of family pets, which instantly makes them entertaining, and they do make pretty cool sounds.
So, imagine this: You’re only one person with no assistants nearby. These helicopters, well, they fly erratically. How do you keep a mic trained on it to get a good recording? I solved this problem before by putting wireless mics on moving objects, but they’re far to heavy for something like this. Well, let’s just take advantage of the toy’s weak flying ability: Why not just hold the stupid thing while the rotors rotate? The rotors, however, rotate really quickly, and move a surprising amount of air. The body of the helicopter is so teensy that I couldn’t find a good mic position that blocked the air being moved around, which of course creates a lot of distortion and rumble.
Rather than futz around with a bulky windscreen and furry windjammer, I decided to just attach a contact microphone to the helicopter with gaffer’s tape. This worked reasonably well, especially after a quick equalization adjustment to overcome the somewhat dull midrange response of the mic itself. The sound that was transmitted through the high-density foam body was actually more interesting and full than the rotor’s sound in the free air, anyway. Besides the aforementioned EQ pass, this recording is unaltered. Recorded at 192kHz, this could provide all manner of mechanical effects if pitched down or processed further!
This wasn't the helicopter I recorded. This is just the only photo of a helicopter I've ever taken! (Shot on the Kaikoura Peninsula, South Island, New Zealand.)
Audio professionals may cringe when they hear this, but I always keep a microphone mounted in my windscreen/blimp/zeppelin, which is always on a short boom pole. No doubt I’ll pay the price when the little mic suspension’s rubber bands stretch and age prematurely, but I like to be prepared for those unexpected moments.
This paid off when I heard a helicopter over my house…much lower and louder than usual. I poked my head outside and could tell the pilot was going in very tight circles over my street. I grabbed my mic rig and my field recorder, and all I had to do was plug in, power up, and hit “Record.” Granted, I happened to have a stereo mic in my windscreen, which wouldn’t have been my ideal choice, but I’d rather use it rather than lose the recording! (Want a horribly embarrassing tale about losing a choice recording opportunity? Read the epilogue after this post’s sound recording.)
I don’t exactly live in a city center, so I’ve got both highway and bird noise polluting most of my backyard recordings. This time, though, the helicopter was so low that the highway was drowned out, and he circled enough times that I was able to do some splicing of the takes to eliminate most of the birdsong. EQ could remove the rest, but I didn’t want to lose the higher-frequency sizzle that I liked in the recording. I did some surgery to make it loop seamlessly, and the result is below.
Epilogue and cautionary tale: I was at a hut on the Kepler Track in New Zealand when a helicopter landed on a nearby pad to drop off some fellow trampers/hikers who were “heli-hiking.” I scrambled for the Zoom H2 in my pack. Through the headphones, the sound was loud, intense, perfectly overwhelming what tiny background noise there might have been. I listened to the chopper landing, idling, and taking off. And then I realized I was only monitoring the entire event, not actually recording. The H2 requires one press of the Record button to arm recording mode, and another press to actually get rolling (a common interface convention in most hand-held recorders). In the moment, I lost track of how many button presses I did, and my fuzzy windscreen prevented me from seeing the time -elapsed readout, which of course wasn’t moving. What is there to learn from this, besides that I’m a complete spastic loser?
Never assume anything. Triple check everything, even if you’re going to introduce handling noise or off-axis sound into the beginning of your recording. Better to have a shorter recording than none.
Gear that’s always in record mode when it’s on is good, gear that audibly gives you feedback when you’re rolling is better, and gear whose display isn’t concealed by necessary accessories is best.
(P.S. The title of this post refers not to what I saw, but the song “Unmarked Helicopters” by Soul Coughing, which has been playing in my head ever since I made this recording. Damn you, catchy melodies, damn yoooouuuu!)
