Sound
made
visible.
Move the cursor across the canvas. The waves follow. Sound is pressure. Pressure is math. Math draws itself.
Four modes. Four ways of seeing the same thing. The frequency is identical. The representation is not.
Enable audio. The visualization locks to real synthesis. The Web Audio API has been here since 2011. This is it.
No harmonic content. The purest tone. If you heard one in isolation, you'd call it a test signal. Every other sound is sines added together.
Jules Antoine Lissajous drew these in 1857 by bouncing light off tuning forks. The same math is still used to tune oscilloscopes. Two frequencies. One figure.
The Fourier transform. Every time-domain signal has a frequency-domain twin. The spectrum IS the sound — just from a different angle.
Polar coordinates. Rhythm as radial symmetry. The mandala is not mysticism — it's math. Culture discovered the equations before the notation existed.
When you enable audio, two oscillators play simultaneously. The first at your chosen frequency. The second at 1.5× — a perfect fifth above. Together they produce a tone with natural beating.
The gain is set at 0.08. That's not quiet out of caution. That's quiet because a sine wave at full gain sounds like a fire alarm. The ear interprets pure tones as extremely loud even at low amplitude. This is physics, not a bug.
Spectrum mode uses AnalyserNode.getFloatFrequencyData()
to read the real FFT of the audio signal. The bars are not approximations.
They are the actual frequency content of what the oscillators produce.
Without audio, Spectrum mode simulates with animated sine waves. The behavior is similar. The data is not. You can tell the difference if you look carefully at the high frequencies.