Sound2Colorby Bryce Borden

Left to right is pitch, low to high. Mountain height is loudness, and anything quieter than the room's background stays flat. Time rolls toward you on the 3D road, or runs left to right on the flat map.

Mountain color (Harmonics) is the job each peak does: red is the main note wherever it sits, then orange, yellow and green overtones above it. Magenta is a tone that doesn't belong to that note, grey is noise, and a white flash is a sudden start.

Timbre, the tone color of the whole moment, has four gauges and shows on the ground:

• Brightness (spectral centroid): the sound's center of mass. It's the color of the glowing ground lane, red/orange for dark sounds and blue/white for bright ones.
• Spread (bandwidth): how wide the energy is spread. It's the width of that lane, thin for pure and wide for harsh or noisy.
• Ceiling (rolloff): where 85% of the energy ends. It's the white ticks on the ground, and the dashed line on the flat map.
• Change (spectral flux): how fast the sound is shifting. It shows as sparkles.

It shows what a sound is made of. It can't tell you what a baby or a dolphin means. Recordings go up to 2 minutes, files up to 3 minutes.

• Ball left/right = the main Hz. It uses the pitch tracker when it's confident, otherwise the loudest peak.
• Ball height = mic level in dB, relative to the phone mic. 0 is the loudest the mic can take, −90 is near silence. This is not sound-meter dB (SPL), and every phone reads a little differently.
• Ball width and the ± Hz = how unsure it is. It shrinks when one pitch owns the sound and holds steady.
• White ring + LOCKED = held within about 1% for 0.7 seconds.
• Green ▲ under the Hz line = where each A note sits (A3 = 220, A4 = 440, A5 = 880 Hz). Each one is an octave, double the Hz of the last, so you can line up Hz with notes.
• Color: Tone (default) = what the sound is like: smooth/pure sounds are blue, rich ones green-yellow, sharp/buzzy/noisy ones red. A flute and a trumpet on the same note get different colors. Color: Note = the old way, one color per note name (all D's yellow, and so on). The note strip on top always shows notes.
• Purple hills = every Hz it hears right now. Small dots = other strong pitches, like overtones or a second sound.
• Tap the graph to drop a green target line, and the readout shows how far off you are. Play target tone plays that exact Hz, so you can check what the phone picks up.
• A human hum has overtones at 2×, 3×, 4× the main Hz. Those count toward "one pitch", so a clean hum can still lock.

• Name that note: 2 choices far apart at first. Then 3, 4, 5 and 6 choices, packed closer together and spread over more octaves. Each button shows its Hz.
• Match my voice: starts with easy notes (C, E, G) and any octave counts. Later it's every half step in your exact octave. "Close enough" tightens from ±50¢ to ±15¢, and you hold it longer (1 s → 2 s). You get 10 seconds per note.
• One miss (or running out of time) sends you back to level 1. Your best level is saved on this phone.

Colors run through the rainbow once per octave, red at C up to violet at B, so the same note always gets the same color. Taller ridges are louder. Birds sing fast, so tap the painting to freeze it and look closer. Phone mics hear up to about 10–12 kHz, which covers most birdsong.