The singer's formant
The singer's formant is an extra peak in the voice spectrum around 2.5–3.5 kHz. It gives trained classical voices their ring and lets them be heard over an orchestra without forcing the volume.
Why it matters
The energy of a symphony orchestra is strongest below about 2 kHz and falls off at higher frequencies. A voice with strong energy near 3 kHz therefore stands out from the accompaniment, even though its overall loudness is not larger.
How it forms
The research of Johan Sundberg and others explains it as a clustering of the third, fourth and fifth formants. When the epilaryngeal tube above the vocal folds is narrow compared with the pharynx above it, it acts as a small resonator of its own and pulls these formants close together, which creates one strong peak. A lowered larynx, a wider pharynx and a narrow epilaryngeal outlet all help.
Who has it
It is most characteristic of classically trained male voices (basses, baritones and tenors) and of lower female voices. In sopranos it is weaker or absent because the harmonics are too far apart at high pitches; they rely more on tuning the first formant to the pitch.
How it is measured
A common measure is the singing power ratio (SPR): the difference in decibels between the strongest peak in the 2–4 kHz band and the strongest peak in the 0–2 kHz band. The closer to zero (or the higher), the stronger the high peak. The tuner in the Voice Lab reports this ratio live from the microphone. It depends on the vowel, the loudness, the microphone and the room, so compare your own recordings with each other rather than with a table.
See it in the model
In the Voice Lab model, lower the larynx and raise the “Epilaryngeal tube” slider towards narrow: the predicted F3 and F4 draw together. This shows the mechanism, not a prescription; do not force a narrow or low position, and stop if anything hurts. For voice problems consult a specialist.
Questions and answers
What frequency is the singer's formant?
Roughly 2.5–3.5 kHz, most often described as around 3 kHz in male classical singers.
Does everyone have a singer's formant?
No. Untrained speaking voices usually do not have it, and it is weaker or absent in sopranos and in many popular-music styles.
Can a microphone and a phone show it?
Roughly. A spectrum or an SPR value shows how much energy is near 3 kHz, but the result depends on the microphone and room, so use it to compare your own takes.
Go deeper: lessons
- Resonance, Formants and Larynx Position — Why a low, stable larynx gives a rich tone, what the singer's formant is, and why the larynx tends to climb.
- The Larynx: True Folds, False Folds, Cartilages — Where the sound is made — and the neighbouring structures (the false vocal folds, the epiglottis) that can help or ruin it.