State Machine
The State Machine provides macro-level compositional form. It divides a performance into sections (states), each with its own parameter settings, and crossfades between them to create evolving compositional arcs.
When Auto-Evolve is enabled, PERF automatically progresses through the state sequence based on elapsed time, smoothly interpolating all parameters between adjacent states.
How It Works
- PERF generates a sequence of 2–8 sections, each with a randomized but musically coherent set of parameters (density, perforation, velocity, pitch range, etc.)
- The state sequencer progresses through these sections over time
- A configurable crossfade ratio determines how gradually parameters transition between sections
- The result is a composition that evolves — building, releasing, shifting character — without manual automation
Parameters
| Parameter | ID | Range | Default | Description |
|---|
| Auto-Evolve | useStateParams | On/Off | Off | Enable automatic state progression |
| Sections | numStates | 2–8 | 4 | Number of sections in the sequence |
| Section Length | avgStateDuration | 15–180 sec | 60 sec | Average duration per section |
| Section Crossfade | gradualRatio | 0–100% | 50% | How much of each section is spent transitioning (0% = instant switch, 100% = fully gradual) |
| Arc Form | arcForm | Random / Golden Section / Arch / Wedge / Corpus | Random | Overall shape of parameter evolution |
| Arc Position | stateProgress | 0.0–1.0 | 0.0 | Manual override for position in the arc |
| Auto Arc Progress | autoStateProgress | On/Off | On | Use time-based progression vs manual position |
| Form | Description |
|---|
| Random | Each section’s parameters are independently randomized. Creates unpredictable, exploratory form. |
| Golden Section | Climax point placed at the golden ratio (≈62%) through the sequence. Parameters build toward this point, then recede. |
| Arch | Symmetric arch — parameters build to a midpoint climax, then mirror the descent. Classical ABA proportions. |
| Wedge | Continuous build from sparse to dense (or vice versa). One-directional parameter evolution. |
| Corpus | Section transitions learned from MusicBERT analysis. Applies statistically natural formal proportions. |
Manual Control
When Auto Arc Progress is off, the stateProgress parameter (Arc Position) directly controls position in the state sequence. This is automatable from your DAW — you can draw automation curves to manually shape the macro form, or use MIDI CC to control it in real-time.
The State Machine works well for generating long-form compositions. Set Sections to 6–8, Section Length to 60–120 seconds, Crossfade to 50%, and let PERF evolve for 5–10 minutes. Record the MIDI output and edit the result.
