I apologize in advance for the wordiness of this post. I'm trying to cover =
a lot of ground. I've got some questions at the end I could use help with, =
but it's necessary to understand why I'm putting myself through some hurdle=
s that might not otherwise make any sense.
I'm interested in recording aerial soundscapes. The motivation behind this=
comes from a couple of sources. First, I've been doing low altitude aerial=
photography for seven or eight years using kites to lift the camera. I'm a=
still photographer, but a couple of years ago I looked into doing video. I=
came to the conclusion that I'm terrible at video, but I fell in love with=
sound. I've been playing with sound on and off ever since, mostly from the=
ground.
Two things happened that pointed my attention back to the sky. One was a h=
igh altitude balloon video that for once wasn't set to music. They used the=
audio off the camera as the sound track. The launch sequence was fascinati=
ng as it transitioned from ground level (voices of the launch crew, kids in=
the nearby park, dogs barking) to low altitude (muted voices with the addi=
tion of nearby traffic noise) to higher altitude (voices and traffic dying =
off, leaving only the occasional airplane and siren) to even higher altitud=
e (the sound of a lone jet flying 30,000' below the balloon), and finally o=
ut to the edge of space (silence).
The other was an aerial video made by a fellow kite aerial photographer na=
med Nicolas Chorier of a street art festival in Pondicherry, India. Nicolas=
flew his kite at a relatively high altitude, but hung the camera only 30' =
or so above the street. This resulted in very stable video, and very intima=
te sound. Every conversation among the artists and the festival goers is cl=
ear.
At that point I knew I had to play. But the more I dug into sound and the =
more I listened to ambient field recordings, the more I realized what was m=
issing from those two videos. They were both made in mono. I wanted to do t=
his in stereo.
One of my earliest aerial experiments was to stick my Tascam DR-05 on my k=
ite aerial camera rig and fly it. It only went up about a hundred feet or s=
o, but even at that distance the stereo separation of the built in mics on =
the DR-05 was minimal. I had other technical issues, mostly relating to EM/=
RF noise of the rig's electronics and servo jitter from the pan and tilt ax=
es, but I had plans to fix those. The stereo problem needed more work.
A few months ago I ordered some EM172 capsules from Frogloggers and built =
several mics. I learned some lessons the hard way, like don't recess the ca=
psules in the mic bodies. I also found that widely separated omnis made for=
confusing sound, even on the ground. I prototyped an SASS out of foam core=
, and eventually built one out of 0.20" plywood packed with carpet padding.=
(I added an album in the photos area with pictures of the mic bodies and t=
he SASS). It works great on the ground, especially with flush-mounted mics.=
But I'm having a tough time making a windjammer for it.
A couple of days ago I started building another array based on Curt Olson'=
s wing design. A couple of things make his design quite attractive for aeri=
al sound from a kite. One, it's smaller than the SASS, and will present a s=
maller cross-section to the wind. Second, if the array is pointed downwind,=
the large bottom boundary surface will help block wind from reaching the m=
ics. But all of this is pure speculation. I've built the prototype, but hav=
en't flown it yet.
Now for the questions:
To fly either of these I need wind. And since they're microphones, wind is=
the last thing I want. I have five kites I fly regularly when doing kite a=
erial photography that let me fly a two pound rig in anything from 6kt to 3=
5+kt wind. Is it even possible to build a windjammer that would shield an S=
ASS from, say, 10kt wind? Or am I better keeping this on the ground and cho=
osing something else, like the Olson wing, to use in the air? I think I hav=
e a better idea of how to build a windjammer for the wing, but I'll still f=
ace the same amount of wind, regardless. Any pointers on what materials to =
use and how much wind I can reasonably block?
I realize that anything you put in front of a microphone will color the so=
und it records. I also get the idea from reading other threads in this grou=
p that heavy post-processing isn't thought well of. However, if my choices =
are to EQ out the effects of a heavy duty wind muffle or not record at all,=
I'd really rather take the EQ and muffle.
Is there anything else I'm missing? Keep in mind I've only been doing soun=
d for a couple of years, and only doing it actively for the last few months=
. I'm still at that point where the learning curve looks like a sheer cliff=
looming over my head. Any and all guidance is welcome.
Thanks for your patience and input.
Tom
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