The exact Gray-Scott chemistry from Media Servers II's Shader Lab, now listening. Bass energy bends the feed rate, treble energy bends the kill rate, and a loud transient drops a fresh chemical seed into the dish — live, from either a built-in synthetic source or your microphone.
This is the same Gray-Scott reaction-diffusion model as the Shader Lab on Media Servers II — two virtual chemicals diffusing across a grid, one feeding the system, the other consuming it — reused rather than reimplemented, right down to the same feed/kill presets (Coral, Mitosis, Fingerprint, Worms, Spots) and the same update rule. It now runs as a real compiled GLSL fragment shader on your GPU instead of a JavaScript loop over a Float32Array: two textures hold the two chemicals and ping-pong each simulation step — one shader reads the current texture and writes the next state into the other, then they swap — the standard GPU technique for a PDE like this one. What's new on top of that: every frame, the Chemistry knobs set a baseline feed and kill rate, and the Audio reactivity knobs decide how far live sound is allowed to push them — bass pushes feed up or down, treble does the same to kill, both always clamped back into the range where the simulation stays numerically stable.
A sudden rise in volume above its own recent average — a beat, a clap, a word — drops a fresh blob of the second chemical into the dish at a random spot, sized by how far above baseline the sound was and how far the inject knob lets it go. With no sound at all the dish still evolves: an internal synthetic source (a few slow sine "instruments" plus a periodic pulse) drives the bands so the instrument is alive the moment it loads. Click Use Microphone to swap in real audio — nothing is sent anywhere, the analysis happens entirely in your browser.
The dish's original fixed color tint is gone too — it's colored with Palette Synth's own cosine-gradient formula (its Ocean coefficients), now evaluated inside the display shader itself rather than per-pixel in JavaScript, and the gradient's offset drifts slowly with the mid band, the one meter reading the Chemistry and Audio-reactivity knobs don't otherwise touch. So the pattern reacts to bass and treble, and its color breathes with the mids.
Fourth instrument in the visual-synth family started by Palette Synth. The Complex-Plane Fractal Mapper closes out the roadmap, borrowing the same cosine-gradient formula to color what it finds.