formante

A formante, or formant in English, refers to a resonance frequency of the vocal tract that shapes the acoustic spectrum of speech sounds. Formants arise from the vocal tract acting as a filter on the glottal sound source produced by the vocal cords. They are not the pitch of the voice (fundamental frequency) but rather the peaks in the spectral envelope that characterize vowel quality and other voiced sounds.

Formants are primarily determined by the shape and configuration of the vocal tract, including tongue position, lip rounding, jaw opening, and velum setting. The most important formants for vowel identity are the first two: the first formant (F1) is generally associated with vowel height (how open the jaw is), while the second formant (F2) relates to tongue advancement (frontness or backness). A third formant (F3) can aid distinctions in some languages or speakers, but F1 and F2 are the principal cues for most vowel classification. Formant frequencies vary across speakers, languages, dialects, and speaking styles, and are typically measured in hertz.

Analysis and applications: formants are estimated from recorded speech using spectrograms, linear predictive coding, or other spectral analysis methods. They play a central role in fields such as phonetics, phonology, speech synthesis, and automatic speech recognition, where accurate modeling of formant structure improves vowel perception and intelligibility. In singing, a related concept, the singer’s formant, is a concentration of energy around 2–3 kHz that helps a voice carry over instrumentation.

Formants thus reflect the physical configuration of the vocal tract and underpin much of the perceptual differentiation of vowel sounds.