Classical and Belting Resonance Stratgies

The resonance strategy used by classical female voices in their middle range is to have the second formant of the vocal tract resonate the second harmonic (F2/H2) of the sound spectrum produced by the vocal folds (phonated tone).  The higher one sings the higher the fundamental rises and so do all of the harmonics of that pitch.  Eventually the second harmonic is too high and cannot be resonated by the second formant.  Keep in mind that formants, which are the resonating potentials of the vocal tract, do not change their pitch.  The pitches of formants can only be altered by changing the vowel being sung.  All vowels have their own individual formant frequencies.

Once the upper threshold of the middle voice is reached using F2/H2, the female singer must change to having the first formant resonate the fundamental of the phonated tone.  This is referred to as F1/F0, with F0 as the fundamental.  Tuning the first formant of the vocal tract to the fundamental is achieved by opening the mouth wider  as the singer goes higher and thus raising the pitch potential of the first formant to follow the rise in the pitch of the fundamental.  This process gives the female voice about a 10 times increase in vocal efficiency according to Sundberg and it is the reason the operatic female voice grows in power and dominance from this range and higher.

But, the belting voice follows a different resonance strategy in the upper middle range and above. Instead of having the first formant resonate the fundamental, Titze found that belters use the first formant to resonate the second harmonic ( F1/H2) at pitches in the range G4-D5  (see ref) . This is just below and above the upper threshold of the classical middle voice.  F1/H2 tuning gives the belting voice an emphasis of higher harmonics, especially on pitches above the “upper threshold” and the effect more closely resembles a female yell or scream when compared with the tone of the classical voice in this range.  If the classical female voice must open the mouth to raise the first formant high enough to track the higher and higher fundamental, then by comparison the female belter must not only open the mouth wider but also widen the smile and raise the larynx and even lift the chin to achieve a high enough first formant resonance potential to tune to the second harmonic.  Keep in mind that the second harmonic of any pitch is much higher than its fundamental.

With such an open ending of the vocal tract from this belting posture, I cannot imagine that any form of standing wave could be produced that would provide a greater transfer of vocal fold energy into sound.  Fortunately, at this time belters, unlike classical singers, are usually amplified which removes the necessity for them to over sing and aggressively stress the voice

Iitze, Ingo: Formant Frequency Shifts for Classical and Theater Belt Vowel Modification, Journal of Singing, January/February 2011, Volume 67, No. 3, pp. 311-312.

Leave A Comment...