# Same note, three sounds

> Three sounds with the same 220 Hz note. What makes each one sound different is timbre.

Acoustics · October 22, 2026 · Pedro Cormann, Founder & Machine Learning Engineer · https://lero.studio/research/en/timbre

Every voice has a note, F0, the frequency at which the vocal folds vibrate. But the note alone does not tell whose voice it is. Timbre does: which harmonics exist above the note and how strong each one is.

_(Interactive on the page: https://lero.studio/research/en/timbre)_

The sine has only the note and sounds like a whistle. The vowel has thirty harmonics, stronger where the mouth resonates, and already sounds like a voice. The noise has no note at all: it is the air of an "s". Each person's voice is a unique pattern of harmonics and formants. That fine detail is what a synthetic voice must keep to sound like someone, not like anyone.