My wife's family thinks I am a little weird. In the course of any given long weekend or family holiday one of them always manages to catch me in some corner or other, holding a microphone, recording some sound that doesn't seem worthy of attention. I am always asking them to be quiet for a moment, and though they always indulge my requests, the eye-rolling is almost audible. Thankfully, they put up with me, and once in a blue moon I'll uncover a co-conspirator in their midst.
During a stay at the family cottage last summer, while I was setting up to record something, my father-in-law sidled up to me and asked, mysteriously, if I had ever heard his 'homemade upside-down fireworks.' Hesitatingly, I answered that I had not and, for that matter, I had no idea what he was talking about. With a mischievous smile he told me to follow him outside. I grabbed my mic and recorder and gave chase.
Outside on the gravel driveway he had collected a peculiar kit: a long branch, a bunch of plastic grocery store bags and an acetylene torch. I had no idea where this was going but I was certainly intrigued. He wrapped the plastic bags in a big clump around one end of the long stick and then used to the torch to set the bags on fire.
Once they were really in full flame, he raised the long branch high in the air and the plastic melted apart and started to drip down about ten or twelve feet to the ground. Suddenly the plastic drops were making the most startling sound. Kind of a mix between a barking seal, a metal zipper and a whoosh. Take a listen:
I am not exactly sure how melting plastic can make this sound but it was pretty awesome and totally unexpected. I am guessing that one thing that contributes to the sound is that the drops don't seem to fall straight down but rather they fall in a tight spiral. You can see the spiral in the smoke trail in this picture.
I quickly realized that by using my stereo shotgun microphone (Sanken CSS-5) and turning the mic perpendicular to the ground I could get a pretty strong stereo pass-by as the drips fell past the mic, right to left, on their way down.
Sadly, when all this was happening in the mid-afternoon, the surrounding environment was relatively loud, so the sounds I was getting were not really useable. There was a heavy rustle of wind through the surrounding trees, bird calls and boat traffic on the nearby river. So I filed the sound in the back of my mind and waited for a better time to record these Upside Down Fireworks.
That opportunity came a few weeks ago. Now that we are entering winter here in Canada all the leaves are off the trees, the birds have mostly fled south, and boat traffic on the river has tapered off as the ice creeps in. I asked my father-in-law if he could give another demonstration of his homemade fireworks show and he was game. This time we did the recording session after dark to get the full effect of the of sound and light together. In the chilly air the plastic drips' volume was amplified and the drips fell at a much faster pace. Here is a section of the faster upside-down fireworks going crazy:
In the darkness it was a pretty bizarre sight to behold. Essentially you could see a ball of flame floating about twelve feet in the air and hundreds of tiny flaming shooting sparks falling down to the ground. The tail-end of this video will give you an idea of how it all looked on that night.
When I imported the recordings to my workstation I moved on to the challenge of isolating the sound of the falling drips. The second recording session was free of environmental sounds, but the sound of the flaming plastic at the end of the stick remained an obstacle. The constant flame gave off a hiss but a surprisingly low frequency one and I was able to to almost completely eliminate it with a combo approach involving an EQ and IzotopeRX. The other sound bothering me while I was recording was the sound of the dripping plastic landing on the gravel driveway. I realized that there was no way to minimize this. If I put something soft down to cushion the impact I would run the risk of the cushion catching on fire. If I put water there it would sizzle and hiss as the drips made contact. So I decided to try to embrace the sound and put a mic on the ground near where the drips were landing to see what I would get. Here is a chunk of that recording.
I'm not sure what use I'll find for this, but maybe one day I'll need some sort of alien rainfall or something. With a little work I can edit the ground impacts out of the main recording.
These sounds will make great sweeteners on a ton of different things in future projects, I am sure. Bullet whiz-bys, Sci-fi vehicle moves, CG title sequences... there's a million other possibilities.
Thanks to my father-in-law, Don, for sharing his amazing pyrotechnics.