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Learning Space dedicated to the Art and Analyses of Film Sound Design |
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FilmSound.org |
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| How to make underwater
sounds?
Frank.Casaretto:
David Farmer: The actual sounds we hear underwater are drastically different than what we "enjoy" in our daily lives, or in a film experience. There's no such thing as "stereo" underwater. Since sound travels so much faster in water than in air, our ears don't know how to distinguish the timing difference, so we can't locate point of origin as being left, right, or the much overlooked up/down. This is evident when diving, when someone is trying to get your attention. You're taught to tap on your tank with your dive knife, (since yelling "hey!!" isn't an option underwater, especially with a regulator in your mouth). I can't tell you how many times I've heard this sound, and tried to locate where it's coming from, and not been able to. Sometimes I can't even find the person doing it. It's a strange sensation, as we're in an
environment that we're so poorly equipped (physically) to observe.
The sound, even if distant, sounds like it's taking place "inside" your
ears (which isn't far from the truth, considering the density of water
vs. air).
Historically speaking, underwater sounds are very muffled, as if water mutes high end. This is of course exactly backwards from what water actually does. But the audience has grown accustomed to hearing muffled sounds underwater, so they will expect that to some degree. We're used to hearing the "dark"
dreamy whale songs that have unearthly echoes. These are beautiful,
but they are also very distant. Recordings of whales that are close
will exhibit an entirely different "clicky" character.
Randy Thom: I agree with david. Everything i have heard done with a hydrophone or similar is very pinched & hi-midrangey. I've had the best luck with pitch shifting normal water down octaves for ambient stuff and using a vocoder w/ chorus and reverb for "hard" effects. really there is no hard fast rules because each source comes out to sound differently through experimentation. I suppose using heavy & drastic eq along with nice smooth reverb to hydrophone stuff may work, but I always ended up going different routes in the past without access to heavy eq (pre pro-tools days). Frank's questions about underwater recording remind me that lots of the the ground to be covered in this group has already been covered by other groups. In case anyone here isn't aware of it, there are at least two other places on the web where people post questions relating to sound in media.
Basically, Frank, most people use
normal microphones sealed in (non lubricated) condoms to do underwater
recording. Just stick the mic far enough under the surface of the
water so that the open end of the condom isn't submerged because
there is no way you can make it completely water proof. You might
be able to find someone who has an actual hydrophone and borrow it.
(I wouldn't recommend buying one for a single project, unless you
are rich.) Hydrophones tend to be noisier than acoustic mics.
Harry Cohen Some folks I know at a facility called EFX recently did some underwater recordings ; they rented an underwater speaker , called a tactical transducer , from a company called Clard synthesis (clarksyn.com) , which had a very wide freq response . they borrowed a hydrophone , and played all kinds of stuff thru the clark transducer for the hydrophone to record . They got some interesting results . Myself , I have used the mic in a condom method , and have played sounds back into a floor monitor layed on top of a plastic pool cover , over at my parents house . My father thought I was absoutely out of my mind. Charles Deenen:
Pluk:
Read also "Sound Design of The Hunt for Red October" at http://www.filmsound.org/articles/redoctober.htm
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