A normal mix places sounds across a line between two speakers. This one places them in a sphere, and the listening format is decided at the very end rather than at the start.
Roughly twenty sources, each encoded individually into a second-order ambisonic field with its own room encoding and directivity shaping, so a source has a position, a radiation pattern, and a room it is in. Reverberation is applied by a feedback-delay-network reverb operating inside the ambisonic domain rather than on a stereo bus, which means the reflections are spatial too.
From that one scene the piece decodes two ways: to a loudspeaker array by all-round ambisonic decoding, and to headphones by binaural decoding. Same scene, two renderings.
Listen
Headphones recommended.
| Rendering | Audio |
|---|---|
| Ambisonic decode |
Where the sound came from
All source material was recorded for the piece. Field recordings on omnidirectional capsules. Tetrahedral-microphone material converted from A-format to B-format before encoding. And instruments from the Baschet brothers' Structures Sonores — the mid-century French sound sculptures built from glass rods, steel, and inflated metal cones, where the resonator is the size of a piece of furniture and the radiation pattern is nothing like a conventional instrument.
That last part is why the directivity shaping mattered. A sound sculpture does not radiate like a point source, and placing one in a virtual room convincingly means modelling how it throws sound, not just where it stands.