Binaurals

One of those little miracles sitting right there in front of us everyday, which we miss because we're usually too busy in the soap opera of human relationships, is what's sometimes called holophonic sounds, or binaural recording. I came upon this when chatting to people about stereo photography, and wondering whether the same thing was possible for sound. They thought no, including Brian (May, guitarist from Queen who's a stereo photo nut).

But as it turns out it's not only possible to 3-dimensionalise sound in the same way you do with stereo pictures for images, it's much easier to do it with sound, and what's more the outcome is not just stereo, but holographic (or holophonic, because it's sound - phonic - rather than image - graphic). You simply use two microphones placed either in your ears or in the ears of a dummy with replica human ear shapes (see pic above), and when you play back what's recorded the sound is holophonic (i.e. completely 3D, as if you were there, the full soundscape surrounding you from all directions, with all the directional and other cues).

You need to use earphones to get the effect i.e. if you listen to what's recorded through speakers in a room you'll still get the sound, but with none of the holophonic features. The experience isn't one you'll forget in a hurry, and for the recording of concerts for example it can actually reproduce being there, at least in sound. I think it's the Milwaukee Symphony who now offers many tracks in binaural (don't quote me, but I'm sure it was one of the American orchestras).

Here's a tasty set of samples, but remember to use headphones/earphones, or else it won't work.

Of course 'surround sound' as you hear in movies and on some audio discuss these days is an attempt in some ways to achieve this effect. But a needlessly complex attempt that doesn't achieve holophony - a pair of binaural mics can be had for less than $100. Although there are other effects surround sound can be used for that are unique to it.

I've had similar inklings in my ongoing wondering about 3D photography, the theory of which is wrong, I'm fairly sure. And I'm sure holography has some interesting link there too. An alternative theory is slowly forming somewhere there, in between all the other things to get done every day.

[Incidentally Brian remembered that Queen had actually used dummy head recording, which didn't really surprise me. They were the cleverest band on the planet, and so completely misunderstood, by so many. Oh, and there's another equally extraordinary type of soundscape that goes under the tag of binaural, which works by entraining brainwaves. I'll talk about that one some other time.]