Genesis

Genesis explores a set of sound synthesis procedures built from stochastic, chaotic and network-based functions. Each generator is a short program that produces continuously varying waveforms and places them within a predefined proportional structure. Koenig described electronically produced sound as "both a form-section and an acoustico-musical unit, a quantum", highlighting its role as both the part and the whole. The piece considers the continuity this idea implies and the tensions it introduces. It reflects on the scope of decisions, selections, and rules, and how these interact through the processes that make up the piece.

1Structure

The strutural sections are constructed from a single unit through the ratios 4:5:6:7:9:11:13 taken in the order below.

Fig. 1

2Material

Each section presents one generator as a constant stream. The generators write the waveform itself, point by point, from a list of amplitudes against a list of durations counted in samples.

Fig. 2Basic principle. A waveform written from two lists. The amplitude list are unrelated to the nothing about pitch that is created from a duration list. Open full size

Fig. 3Folding the stream. Three amplitudes taken round and round, which are close to a square wave. Everything else happens at the fold, where the stream is reflected back every time it crosses a threshold that is itself moving. Open full size

Fig. 4One sample a segment. The same engine with the durations taken to the limit. One control multiplies every duration at once and sweeps the material from a tone to broadband noise without altering the amplitude. Open full size

3Walks

The same principle with the next point chosen by a walk rather than read from a list, so the waveform has a memory of where it has been.

Fig. 5Drifting waveform. Every breakpoint of the cycle remembers where it was and steps from there, so the shape never repeats exactly. stiffness decides how far it may leave the fixed shape it is pulled toward: at 1 the waveform is chosen, at 0 it is found. Open full size

Fig. 6Chaotic scale. Each breakpoint carries its own chaotic oscillator. The tether scales how far the chaos may take it, and a second tether does the same for the segment durations, so the period can be locked or left to breathe. Open full size

Fig. 7Bounded waveform. The tether removed. What keeps the waveform in range is what happens when it reaches a bound, and the two bounds can behave differently: reflect, wrap, hold, or throw the walk somewhere random. Open full size

Fig. 8Written waveform. The grain is itself a written waveform, redrawn between emissions rather than inside them. Open full size

4References

GenesisThe SuperCollider code for the piece: the generators, their presets and the tools for playing them.github.com/bjarnig/Genesis
TetherExperimental SuperCollider UGens for digital synthesis, the generators used in the walks.github.com/bjarnig/Tether