Formants are spectral shapings created from an acoustic resonance of the human voice tract. These are amplitude peaks in the spectrum of resonant sound sources. Even more so, they are a concentration of acoustic energy that flows around a specific frequency in the speech wave. There are a variety of them and each one corresponds to a resonance in the vocal tract. Overall, these are a great addition to timbre tonal musical instruments and they are typically in-harmonic.
The Vocal Tract
Formants generate in the vocal tract. The air inside the vocal tract tends to vibrate at different pitches depending on its size and shape. Articulators modify vocal resonances to create peculiar vowel sounds. The peaks formed in the vowel spectrum are the formants themselves.
The process of articulation determines the frequencies of the vocal formants. The tongue, the jaw, and the lips play an essential part in the process. Even when you alter the frequency, formants tend to stay the same. In order to generate different vowel sounds, it is necessary for the formants to return to a general range of frequencies.
Formants and Music
When talking specifically about music, when the formant alters, each musical instrument produces a unique sound. Even the slightest modification can result in a totally different frequency, giving place to a distinctive tune. That said, the timbre varies as a result of the peak’s position. As a result, different positions produce different formants.
Generating vowel sounds requires resonance. Each vowel sound characterizes by a different set of formants. In addition, you can place it artificially on a complex sound by using one or many resonant filters. In order to create vowel sounds with multiple filters, the sound source needs to contain a certain frequency content in a specific formant range.
The quality of the sound is a result of the formant region. The frequency stems from where the sound improves by the cavity resonances of the human vocal mechanism. The inner ear is capable of distinguishing specific vowel sounds. In contrast, formants distinguish vowel sounds at different frequencies, regardless of the pitch.