Musical Idea 7: Spatial Dance
11.16.2013 § Leave a comment
There are a number of great minds working on spatial sound these days.
In one camp, we’ve got composers like Georg Friedrich Haas continuing to expand on a relatively young line of experimentation (including heroes such as Henry Brant, Iannis Xenakis, Charles Ives, Edgard Varèse, Karlheinz Stockhausen, and others) with placing live performers surrounding or even among the audience. It’s partly semantic, such as in abolition of the performer-audience power play per Glen Gould, I think, and partly about the pure acoustical experience here.
In another camp, we’ve got ambisonics working in 4π steradians, the litero-physical ultimate in surround sound (coming at you from any direction). Also wave table synthesis, simulating sounds from any distance. These technologies require specifically advanced auditoria to transport you to their worlds.
In a third camp, we’ve got binaural sound working to bring these types of directional and distantial experiences into the comfort of your own ears. By replicating the various transformations that sound waves undergo depending on how they hit your pinna and bounce down your ear canal, which your brain has developed to associate directionality with, your brain can be tricked into interpreting the sound as actually coming from different directions (look up head-related transfer function, HRTF).
All this is good and well, and in fact without these awesome musicians and technologists doing their things, there would be no point in me writing this article. But this article is not about these techniques for creating the listening spaces where sound can be experienced spatially. I am going to write about techniques for exploiting such space, within it, once it has been created in the first place.
As a film maker I am biased toward the second camp: I imagine bringing the people to a place where they sit peacefully in one spot and let media assault them, a place void of, on behalf of the audience, any concern for the minds of any live performers or fellow audience members; any performance-related sounds are simulated. I can’t limit my scope to merely expanding upon traditional orchestration, as Brant has. Like film to his stage play, I want to cut and pan and zoom and all manners of throwing the audience’s minds around with terribly precise yet wild vectors in some psychotic aural space.
Some time ago I was given the privilege of using a friend’s extremely high quality canalphones, and it was no less than a revelatory experience. It was as if the music to which I was listening existed in the same conscious space as my own internal dialog or—as I fondly refer to it—my “mind’s ear.” I am aware now that this is commonly considered an undesirable effect, and that much research has been put into developing algorithms for externalization. I think therein is a sign of the difference between myself and the majority. I don’t want to simulate being in an external performance of any kind. I want to create something more like a godlike universe-mind of sound. Of course, I’m aware of the awesome power of feeling huge sound waves pounding my body, and how it feels to move one’s head through a field of diffusing and interfering signals; for me, however, the ultimate forum for musical experiences involves no interactivity: it is blindfolded, prostrate, with another mind’s sounds superimposed onto my own. So we’ll also set aside interactivity for now, though spatialization certainly lends itself to non-only-recipient-ness. Basically I just want to cover some motion primitives, and give some example applications to sound.
So to begin, composing in spatiality, you could have all entities moving erratically anywhere to create a chaotic effect. That would be one extreme, and not a particularly interesting one. Or you could simply choose some static coordinates for each entity and have them never move from there, like a normal performance with the player rooted in a seat but with those seats hovering here or there above, below, and around us. That would be the other extreme, also not particularly interesting. Probably most interestingly, you could compose somewhere in between: the positions of the voices in the music change throughout, but in an orderly, not (entirely) noisy way. The spatiality becomes a new compositional component, minding the others, interwoven with movements in pitch, duration, timbre, etc.
Oscillation: the entity moves back and forth between two points. These can be vertical, left to right, front to back, or any angle. The path can be the shortest path between two points, straight; or it could be wiggly, or arced like a pendulum. It can either smoothly accelerate and decelerate into and out of the changes in direction, or it can just move at a constant speed like a simple computer. It can even resemble a bounce on one or the other sides by moving fastest coming out of the direction change.
The entity can just pass on through, shooting by, at a distance, or as if right between our legs. Maybe as it goes off into the distance in one direction it always comes back from the other, as if space is looped toroidally, or even some strange mapping of fundamental polygons like the twisty pentagonal faces of the icosahedral Seifert-Weber space which our own universe arguably boasts. Or like a spherical projection where infinity in any direction loops back to the centerpoint, so there could be waves of sound emanating out of us only to channel back through us, infinitely recursively turning inside out.
Combine the two ideas: oscillations straddling such portals. Out the right and in the left, change directions in the middle, back out the left and in the right.
Entities can orbit us, changing speeds, changing distance (and not merely elliptically), changing incline, spiraling back in then out then back in, or orbit something else, or more than one thing. Maybe like a figure 8 with one half screwed 90 degrees around, or take a figure 8’s other line of symmetry and turn that 90 degrees, stretching it like mad, Bezier’ing out the corners. Cardoids, tractoids, trochoids.
Entities can move in compounds of these, like a helix, orbiting a point moving orthogonal to the plane of orbit. More than one entity can dance together, like a double helix, and maybe even another bouncing between them. Mutual orbiting. A piston engine converting reciprocating motion into rotating.
Entities follow an arbitrary path, arbitrary except that they keep choosing it or getting sucked into it, bringing meaning to it.
We could perceive things like gravity or magnetic resistance acting between entities. Give the soundscape a full-fledged physics engine. Give it vacuums, cannons, wormholes. Entities collide. Entities on centrifuges. Particle simulation, surface tension, stacking and collapsing, tilting and rolling, slipperiness and coefficients of friction, air pressure for lift, liquid flux, etc. etc.
Get enough entities dancing together at once and the emergent effects can become a thing of their own. Cellular automata. Give them some simple rules and set them loose. Sounds trying to pass each other on the sidewalk. Listen to traffic, or Brownian motion, bubbles of oily sound in watery sound.
Maybe the entity is like a directional speaker, and thus its orientation matters in addition to its positioning. It may rotate as revolves, or aiming at or tracking other entities. Some entities might be sound absorbers or sound mirrors instead, working together or against each other to create new effects.
The reverb and echo aspects of entities could behave independently, as if comet trails.
Or maybe rather than thinking of ourselves as situated while the entities dance about us, we dance around a stable world of sound objects. Or perhaps both our vantage and the entities dance together.
So far I have spoken here of spatial sound only dancing with itself, independently from other musical parameters. But that’s where things start to get super interesting!
The mappings between space and sound could be as simple as simulating conventional reality. The high pitched could be made quiet and distant, while the low pitched ones sound near and loud, as if we’re situated on the ground and the entities are dive bombing and bouncing from on high.
Or the mappings could be more or less just attributing an extra spatial distinction to an existing musical effect. An ostinato could make an orbit each iteration. An entity could complete a pitch circle in accordance with completing a loop into distant left from distant right. Maybe an entity changes timbres or personalities depending on where it’s located.
Or the mappings could be more abstract, such as the tightness of a rhythm slacking when its entity is traveling quickly. Or each pitch interval is associated with a completely different movements, like a fifth causes a spin jump while a third causes a somersault.
In all seriousness while I’d thought about this stuff before, I just streamed these out typing on my smartphone while sitting in a no-connectivity hospital waiting room, so I’m sure there are countless more examples. I just hope to start you thinking.