How Do Operatic Tenors Sing Their High Cs?

07 Jun How Do Operatic Tenors Sing Their High Cs?

A clear answer to this question is not easily found. I will offer some of my own thoughts, based on my research, but comments and suggestions are very much welcome.

Limited information is available in books, articles and several websites, but often of the type “smell the roses”, “guide your sound as an arrow”, “avoid vertical thinking”, or similar, not really addressing the problem of “how to”.

In his book “The Structure of Singing” (page 117, Schirmer), Richard Miller states that theories dispute about the way tenors sing the notes above A4, and in his “Training Tenor Voices” he admits that the tenor voice remains a mystery to most audiences and teachers alike.

Of course, every respectable voice teacher had succeeded in training tenors and their range extensions. But how the extension is actually achieved, and what adjustments are made in the vocal tract is shrouded in mystery.

The reason for the enigma may be in the fact that there are different ways in which the range can be extended. Singers find it difficult to explain how they achieved it, because most (if not all) of them learned to sing their top notes by empirical methods, by “a semitone a year” approach – they attempt to extend the range by a semitone under the supervision of a teacher, the vocal system eventually finds a way (perhaps one of many) by adjusting and strengthening the musculature with satisfactory acoustic result, and the teacher/student then fix it by repetition until it becomes the new reliable highest pitch. They then proceed to the next higher semitone in a similar manner.

There are several potential problems with the approach. A young tenor can extend by shear youthful strength and vigour, but the high extension so obtained may not be sustainable in the long run. The extension can be reached by a mechanism that offers a high C of a limited quality, with deficiencies that will show later in the career, when singing in large concert halls or on operatic stages. In other words, there are prerequisites and accomplishments that need to precede the range extension effort and enable the development of a sustainable elite tenor sound. There are quite a few of these preconditions – a low and relaxed larynx, an open throat, creation of space, a convergent vocal tract, the engagement of external laryngeal musculature, the epiglottal squeeze … There is a substantial set of skills, and we address in our “Voice Science in Vocal Pedagogy” Workshop.

Let me discuss here the possible vocal mechanisms that can be used to extend a tenor’s range to a high C and beyond.

Tenors can carry the head voice to at least about A4. What happens thereafter is largely unknown. The vocal folds are fully stretched by the maximum activity of the cricothyroid (CT) muscle and the resulting laryngeal tilt; not much can be done internally in the larynx in order to stretch them further. Or can it? What sets the limit to the action of the CT muscle? Is it its strength, or maybe the space for the tilt is limited? Many pedagogues would nowadays be aware of the need to strengthen the CT muscle, so let us assume that the former is not the case, and that the options for extending the range are:

• Option (1): increase the stretching of the folds (other than by CT-induced laryngeal tilt);
• Option (2) increase the tilt (again, without additional involvement of the CT muscle).

Addressing option (1): Is there another way to lengthen the vocal folds by an action of larynx’s internal musculature? Well, yes, there is one alternative method – by using falsetto, and by falsetto I mean the register that sits above the male head voice – in other words beyond the range of the normal modal voice, mostly in imitation of the female voice, whereby only the ligamentous edges of the vocal folds vibrate.

A few words about falsetto: the vocal folds are kept in place by the balancing act of the vocalis muscle (the muscular body of the vocal fold), which pulls them forward, and the posterior cricoarytenoid (PCA) muscles that pull them backward.

Falsetto is produced by completely relaxing the vocalis, which action then allows the PCA muscle, facing no more resistance, to flip the arytenoid cartilage backwards and further extend the vocal folds into a still more elongated (and loose) position, not closing the airway completely and producing a thin, breathy sound. The “reinforced” falsetto is an upgraded version of the falsetto, created by training the lateral cricoarytenoids to more completely close the gap in the folds while still keeping them in the elongated falsetto position. Males, especially baritones, can produce an impressive imitation of the soprano voice that way.

The backflip of the arytenoid cartilage is an on/off movement for most singers, meaning that the cartilage is either flipped back or not, and that the voice produced is either the head voice or falsetto, nothing in between. And here comes the question: do tenors, with appropriate training, learn how to gain control over the flip, so that the arytenoid cartilage is only flipped half-way – producing the tenor sound, something between the head voce and the falsetto – a “mix”. The control may be subconscious, the singers developing it without knowing. Is that what really happens? Is there a way to teach the “half-flip” explicitly?

Richard Miller stated that “some theorists think that tenor’s voice above A is a reinforced falsetto, while the other deny the use of falsetto at all”. The knowledge of physiology favours the former – that the high tenor voice includes some of falsetto mechanisms. But which one?

A useful insight, a rare one on the subject, was offered by the well-known American laryngologist Dr. Leo Reckford, a therapist of many Metropolitan Opera singers, as described in Jerome Hines’ book “Great Singers on Great Singing”. Dr Reckford comments that tenors “singing a C sharp or a D definitely start with falsetto but being able to put more air pressure on it, the vocal folds come closer, and much more than the edges vibrate”. This sounds like the description of a super-reinforces falsetto, a mix of head voice and falsetto.

So, of the two mechanisms, the super reinforced falsetto and the arytenoid half-flip, which one is actually used by tenors? We do not know for sure, perhaps both. More research is needed, but if I had to cast my vote it will be for the half-flip. Here are the reasons:

• Even an advanced student has to work hard on his extension; however, his lateral cricoarytenoids must have already been developed, so he should already possess the muscular support needed for the reinforced falsetto – it has to be something else in his armoury that is missing.
• If you listen to an elite tenor ascending beyond a C or C-sharp you will hear the transition to the reinforced falsetto – it is not the voice that he uses to sing the high C.
• The tenor “sob”, the soft, emotional, crying tone onset used for effect by tenors (and no other voice) seems to testify that the tone starts as a falsetto and is quickly changed to the mixed, or to the head voice.
• If a relatively skilled singer transitions from falsetto to the head voice on a constant pitch, he can do it slowly, indicating that the movement from a backflipped to the normal position of the arytenoid cartilage can be made gradually. It stands to reason that the singer can be trained to control the extent of the flip and keep it half-way or so, to produce the falsetto/head mix.
• Even a professional singer’s voice can “crack” on a high note, and turn to falsetto. What is logical to conclude is that the singer did not manage to controlled the arytenoid backflip well enough and remained in falsetto.

Addressing Option (2): What can we say about the extension of the head voice by enabling more laryngeal tilt by using muscles other than the (already fully engaged) CT muscle?

Trained singers extensively use the larynx’s extrinsic musculature (the neck muscles), mainly to assist the laryngeal tilt and to counterbalance the action of the elevators of the larynx, so to keep the larynx in a stable, low position without depressing it with the tongue. For range extension, however, the routine use of the extrinsic musculature is probably not sufficient, and some other options that are available need to be utilised, for which specific training may be required. The “tracheal pull”, and the engagement of larynx’s suspensory musculature, especially the sternothyroid and the cricopharyngeus muscles in a specific way may be the examples.

What are the pedagogical implications of the above?

Much of vocal training is of holistic nature – consisting of simultaneous improvement in many inter-related areas. Breathing cannot be separated from phonation, agility from sustainment, support from vocal folds action, etc. However, if we look at how physical skills are trained, we find that there are often opportunities for accelerated advancement by identifying groups of muscles that limit the progress and work on them in isolation, in addition to the normal, holistic training. For example, reaching for high notes regularly in a daily regimen will strengthen the CT muscle to a certain degree, but repeating the drills that target that muscle alone may prove especially productive.

There may be four classes of actions that a pedagogue may consider:

• Make changes and additions to his holistic approach. For example, he may start insisting on a relaxed low larynx, and progress with the range extension insofar it does not cause the larynx to rise; or he may discourage the use of unnecessary high lung pressure, i.e., by not straining as in weightlifting.
• Introduce exercises that aim at supplementing singer’s technique with capabilities that he may already possess, such as the tracheal pull.
• Propose exercises that develop certain muscle groups.
• Introduce and train new skills, like knowing how to control arytenoid back-flip and produce mixed voice of the head and falsetto voices. A purposeful and meaningful practice of the engagement of the external laryngeal musculature may fall into this category as well. It will be aimed at (1) generating more tilt, (2) keeping the larynx low, and may include specific drills. The drills can be directly instructional such as “widen the base of the neck”, or imagery-based such as “think of creating a vowel under the vocal folds”.

Finally, it would appear from all the above that the use of falsetto should be a prominent feature of every tenor’s voice development, employing it for firming the response of the vocal ligaments, and for strengthening the cricothyroid muscle. An inquisitive singer may be interested in the physical details of his range extension, but many will remain unaware of the physiology of it; it is the pedagogue’s job to convert the insight into suitable exercises and drills adjusted for each student. As throughout all vocal studies, the teacher’s ability to “hear” the functionality of the voice is crucial.