Research: Google MusicFX (musicfx.sandbox.google.com) generates AI music
from text prompts but has no public API. Implemented equivalent "sovereign"
ambient soundtrack using Web Audio API — no external files required.
Architecture (4 layers routed through convolver reverb + limiter):
- Sub-drone: two detuned sawtooth oscillators at A1 (~55 Hz)
- Pad: four triangle oscillators forming an Am7 chord with slow LFO swell
- Noise hiss: pink-filtered white noise loop for space texture
- Sparkle: random pentatonic sine plucks every 3–9 s
Wires the existing #audio-toggle button (🔊/🔇) in index.html.
AudioContext created on first click to satisfy browser autoplay policy.
Refs #291
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
