The terms head voice and chest voice are the sources of great confusion in vocal pedagogy. The reason for this is that the traditional schools of singing in the 18th and 19th century did not have the scientific means to make a clear distinction between phonation issues and resonance issues. Consequently, the two terms (probably the most used in vocal pedagogy) are used indiscriminately and often have different meanings in the vocabularies of different teachers. The goal of this post is to bring some clarity to the usage of these terms.
1) Head voice and Chest voice in the context of phonation. The first distinction that should be made is how the terms are used in terms of phonation. Teachers who use the terminology in terms of phonation make a difference between head voice (at one extreme) as being akin to falsetto or flute voice and chest voice as being the loose gutteral utterance we often refer to as raw or open chest voice (at the other extreme). To avoid such extremes in the middle range, such teachers will use the term, mixed voice (I will avoid discussing this at this juncture because it has a resonance component to it).
What is most pertinent to this discussion is the way the vocal folds approximate in these two modes of production. In the flute production, the vocal folds do come together fully. This type of efficiency is desirable. To achieve a balanced modal phonation (a supported tone if you will), adequate breath pressure must be applied without the participation of extraneous musculature. This is perfectly achievable with practice and is in fact the goal of efficient phonation. This is the reason that many teachers advocate the top-down philosophy. It is a logical philosophy.
The open chest mode of phonation is inefficient and cannot be taken very high without causing extreme extraneous tension. This mode of production is a vocal effect that should be used sparingly and only in the extreme low range. Unfortunately, many men as well as women use this mode of phonation in the chest range believing it to be efficient, and that with practice it can be connected to the rest of the voice smoothly. This is not possible. Changing from open chest voice to the fully-adducted flute-like tone can be masked. But the glitch can usually be detected.
So why use the open chest voice? The answer is simple. It requires little coordination. The result is immediate, and singers are not often very patient people when it comes to their voices. Better yet what is the alternative? Am I suggesting taking the flute-based phonation down all the way? Yes and no! To explain this fully, I must also discuss what we mean by head and chest relative to resonance.
2) Head and chest voice in terms of resonance. In resonance we are dealing with two modes. The pharyngeal resonance or Formant 1 controlled by the space below the tongue, and the palatal resonance or Formant 2 controlled by the space above the tongue. These are often referred to as chest and head respectively in the male voice, and chest and middle in the female voice. The male passaggio and the female first passaggio (roughly between B3 and G4) constitute an acoustic phenomenon primarily. Depending on vowel, at a certain pitch level, the dominating resonance switches from Formant 1 to Formant 2. The singer must change the vowel (tongue, lips laryngeal height, palatal height, etc are all involved in the vowel change) in such a way as to accommodate the needs of the Formant 2 resonance. This is the concept of vowel modification. Beyond the female second passaggio (roughly between D5 and G5) the resonance mode should change back to Formant 1 resonance, and the range above the passaggio is referred to as the female head voice. To complicate matters, resonance adjustment has a direct effect on muscular activity in the larynx. This complicity confuses the singer in thinking that a resonance change is in fact a phonational change. Although the two processes are inter-dependent, it is important for understanding to keep them separate.
Now to the question that I previously posed: Do I believe that the flute-like tone should be taken all the way down?” I said yes and no. First, here is why yes:
The flute voice or full closure falsetto that most singers can experience in the high voice constitutes correct fold adduction. There is usually not enough muscular antagonism from the vocalis muscle group to constitute a “real” supported tone. However, one can learn to gradually crescendo from this tone. Furthermore, when one begins in flute or full-closure falsetto and maintain the quality of the tone while descending in pitch, the vocalis muscle becomes gradually active and a true tone is achieved. How much breath pressure can be applied to the tone depends on individual strength, and this can be developed over time. Therefore, in terms of phonation, I do believe that the full-closure falsetto or flute voice should be at the basis of healthy production. This is essentially a top-down approach, and it works only because there is the understanding that the full-closure flute voice must be properly pressurized (increase subglottal pressure and related vocalis activity) in order to be viable. Maintaining the unpressurized flute voice down, will not yield efficiency, but breathiness instead.
Now for the no:
In terms of resonance, there is an acoustic change that is necessary around both passaggios. From the female high voice across the second passaggio, the resonance should change from Formant 1 dominance to Formant 2 dominance. However, the flute-like nature of the phonation must remain. The problem is that the phonation is often lost when there is a resonance change. So the singer who is uncoordinated is convinced that he or she cannot maintain that mode of phonation. The same is true at the lower passaggio (the only traditional male passaggio) around B3 to G4. The change this time is from Formant 2 to Formant 1.
Scientifically, this means maintaining the flute-based phonational efficiency, but changing resonance mode appropriately across the passaggi. This brings me to the concept of a mixed voice. What is referred to as a mix is a combination of the flute-based tone that is traditional called head voice and changing the resonance to Formant 1 in the low voice, which is one element of chest voice. The sensation is that one is going into a different mode of singing in the range below the first passaggio, but one that is somewhat related to the top voice.
To summarize, the phonational mode, flute-based, should be maintained throughout the range, and the resonance mode must change across the passaggi.
Finally, I must also address the bottom-up philosophy. This approach to register unification has been less successful and less popular and there is a reason for this. The nature of the phonation in the low voice must be determined. If the singer has a well-developed mixed voice as explained above (flute-based phonation with Formant 1 resonance), then it is possible to bring this production up relatively easily. But fewer singers have such a coordination in the low voice. Building the upper voice based on an open chest voice is usually detrimental.