# Formants Formants are the resonances of a space, for instance, the human vocal tract.[^1] In speech, they exist below 5000Hz and are usually in-harmonic.[^2] The first formant frequency is higher for open vowels, like [a], and lower for closed vowels, like [i] or [u]. The second formant frequency is higher for front vowels, like [i], and lower for back vowels, like [u].[^1] I wonder if this first and second formant frequency is responsible for complementary frequencies (see [[How to use complementary frequencies]]). F1 corresponds to vowel height, and F2 corresponds to vowel advancement (back or forward).[^3] ![[Average_vowel_formants_F1_F2.png]] ![[formants-3.png]] More about this in chapter five of [[Cantabile]]. [^1]: [Formant - Wikipedia](https://en.wikipedia.org/wiki/Formant) [^2]: [Using Formants to Synthesize Vowel Sounds - SoundBridge](https://soundbridge.io/formants-vowel-sounds/) [^3]: [Speech Acoustics 5 - vowel formants - YouTube](https://www.youtube.com/watch?v=glnUFa2fLyE)