Singing in the Upper Range
Having a well-developed, useful upper range is one of the primary training goals of most singers. They want impressive, powerful, consistent, beautiful high notes. This article was originally a six-part Facebook post discussing the male upper range. Some edits have been made to incorporate the female upper range, as well as 'mixed' voice (as it is created in commercial styles of singing).
IDENTIFYING AND NAMING THE SOUNDS HEARD IN THE UPPER REGISTER
Is it head voice, falsetto, voce finta, underdeveloped head voice, 'whoop,' 'mix,' or belt? Identifying the sounds that we hear in the upper range is challenging for several reasons. To the untrained ear, some of these qualities sound very similar to each other. Also, there is not always agreement amongst vocal pedagogues and singers on the nomenclature assigned to these qualities (e.g. many refer to all clear tones in the higher register as 'head voice,' even though the tuning may not be that which is spectrographically identified as head voice, while others employ the terms 'modal register' and 'loft register' to the singer's scale). Anyone who has ever taken lessons with me knows that I refer to the sounds that I hear by certain names based on their unique physiological coordinations and resonance factors, not simply on the current trends. I have prepared a table that displays these differences between the physical coordinations, resonance tuning, and aurally identifiable qualities of these different types of phonation (sound qualities) for easy reference.
ESTABLISHING OPERATIONAL DEFINITIONS
Let's start by establishing an operational definition of 'head voice' so that we're on the same page. Head voice occurs over a series of fundamental frequencies (pitches) where the vocal folds are stretched and thin, thanks mainly to increased involvement of the cricothyroid (CT) - vocal fold lengthener - muscles and decreased thyroarytenoid (TA), or vocalis muscles, (which are the muscular bodies of the vocal folds) activity. Head voice is sometimes referred to as the 'lighter mechanism' of the voice because there is less vocal fold mass involved in its production. The vocal folds are fully approximated. (Not everyone 'approves' of or accepts the nomenclature traditionally or popularly assigned to this higher portion of the singer's range. However, neither am I going to argue terminology here nor am I going to set about renaming things. It's more important that we are at least on the same page regarding the definition as I am applying it here.) Head voice is usually described as 'bright' and 'ringing.'
Although the terms are often used interchangeably, head voice is not the same as falsetto. In falsetto production, the singer feels no connection to chest voice (because the TAs are relatively inactive), there is typically a gap (either small or large) in the glottis (due to the slackened medial compression that would otherwise be offered by the TAs), and the full spectrum of overtones is not represented, making it less rich in overtones and less capable of dynamic variation than head voice. Additionally, the larynx typically sits in a higher position within the throat. Head voice, on the other hand is CT dominant, but the TAs continue to offer some medial compression throughout at least the lower part of the head voice register so that the vocal folds remain fully approximated. The result is a stronger source vibration, with many (and louder) overtones, that allows for greater dynamic variation. The larynx is generally low (opera) to neutral (CCM). When the larynx is raised (usually in order to continually raise the first formant and maintain speech-like qualities in the higher range) but medial compression is competent, it might be said that the singer is using 'mixed' registration (which keeps H2 BELOW the first formant), rather than head voice (which allows H2 to rise ABOVE the first formant - more on this later).
THE PASSAGGI
There are pivotal notes at which muscular shifts occur. These will be referred to as the two passaggi and/or 'lifts.' (Passaggio is not synonymous with 'break,' which generally occurs above the secondo passaggio in males and between the lower and upper passaggi in females and results from the singer's failure to make gradual muscular, breath, and resonance adjustments when ascending the scale, leading to a point at which a shift of some sort is unavoidable and must be forced.) Singers experience their main 'lifts' (i.e., passaggi and pivotal register transitions) at different pitches depending on the size and thickness of their vocal folds. A singer with shorter and/or thinner vocal folds will tend to be higher- and lighter-voiced than a singer with longer and/or thicker folds. (There are also resonance factors related to the sung vowel's unique formant frequencies that affect the locations of these shifts, which will be discussed momentarily.) This aspect of anatomy, however, doesn't always reflect the singer's range potential, as there are lower-voiced singers who have expansive ranges and are capable of singing comfortably and skillfully for short periods in very high tessituras while some naturally higher-voiced singers have impressive (and sometimes surprising) lower range extensions.
Below are the passaggi locations pertinent to each of the main voice types (corroborated by numerous teachers, including Richard Miller and Anthony Frisell, supported by research conducted by Ingo Titze and others, and witnessed in my own teaching studio). The lower pitches for each voice type represent those with 'dramatic' or more 'robust' voices, while the higher pitches are indicative of 'lyric' or 'leggiero' (light) vocal weights. For the sake of being succinct, intermediate voice types (e.g., baritenor and bass-baritone) are not listed here. These pitches are of primary consideration when classifying voices (along with timbre, vocal weight, range, and tessitura).
As I alluded to earlier and will explain in greater detail momentarily, successful navigation of the entire range depends almost entirely on making graduated shifts over a range of many notes, rather than postponing the adjustments until a shift becomes absolutely necessary (which often leads to register breaks). For this reason, some people talk about the entire range above the lower pivotal registration shift as a passaggio. The singer must always bear in mind that the vocal mechanism must be kept in a dynamic rather than static state. This 'period of adjustment' begins somewhere around (usually a bit lower) than the primo (lower) passaggio and continues through to the secondo (upper) passaggio and in the few notes that follow. These shifts involve a gradual transfer of dominance from the TAs (which control the adduction forces of the glottis) to the CTs (which lengthen the vocal folds), along with some adjustments of resonance and breath. However, the TAs continue to provide a degree of counter tension up until the highest portion of the modal range - an area that some might call the falsetto register, loft register, or super head voice. If they do not, the voice flips into falsetto around the secondo passaggio. Both in response to and in order to assist these muscular shifts, the breathing mechanism and the resonator portion of the vocal tract must adapt (e.g., the configuration for the vowel alters for the given phonation frequency to ensure balanced resonance and mechanical efficiency). The resonator must also adapt to the changing relationships between the frequencies of the voice source (the harmonics produced by vocal fold vibration) and those of the resonator tract (formants).
TRAINING THE UPPER RANGE
There is no ONE way of approaching head voice training that will be effective for all singers and for all aesthetic or stylistic goals. How head voice is trained is largely dependent on the singer's current technical habits. For example, if the singer tends to retain too much TA involvement above the lower passaggio without inviting some increased CT engagement, middle voice and head voice will become unlikely and registration shifts are likely to be more pronounced. The larynx will rise significantly and the voice will become shouty and unmusical, then probably flip at some point into an airy falsetto quality rather than a 'supported' head voice. For this type of singer, a 'top down' approach involving falsetto, voce finta, semi-occluded phonations, nasal continuants, etc. in descending patterns might be in order so that some of the lightness of the head voice can help him/her find correct balance in the middle range (and thus middle voice).
Exercise 1: Rapid 5-4-3-2-1-2-3-4-5-4-3-2-1
In this exercise, the first eight notes are lip-rolled or tongue-tip trilled and the last five notes are sung on an [ʌ] or [ɑ] vowel. The singer should take care to avoid trying to 'support' more for the vowel sound than for the trill.
Exercise 2: [ŋʌ-ŋʌ-ŋʌ-ŋʌ-ŋʌ-ʌ-ʌ-ʌ-ʌŋ] (NGuh-NGuh-NGuh-NGuh-NGuh-uh-uh-uh-uhNG) on 5-5-5-5-5-4-3-2-1
Successful development of the higher register is largely dependent upon what happens in the middle range (between A3 and G4 for most male voices and D4 to G5 for most females, with the lower notes being more pertinent to basses and contraltos and the higher notes to tenors and sopranos, respectively). The singer must learn to anticipate and respond appropriately to the very subtle breath and resonance shifts that need to take place throughout the zona di passaggio (in males) and middle register (in females) - the area between the two passaggi. The approach for a singer with limited or no access to the lighter mechanism (either head voice or falsetto) would differ greatly from that taken by the singer who can already access this part of the range, even if it is yet underdeveloped. Voice type (especially natural vocal weight) may also be reflected in the singer's tendencies. Even though the same physiological and acoustical principles apply to all voice types and registration events are nearly identical (in happenings, not in location), there are nevertheless some subtle differences that can make a world of difference in helping the singer of a given voice type develop his/her head register. Voice training is highly individual in so many respects. Some approaches seem to work better for some students than for others.
RESONANCE FACTORS
Oftentimes, we tend to think of registration as being a purely physiological phenomenon. While there are certainly physiological changes that take place within the larynx as pitch ascends and at the pivotal registration event locations (the passaggi), including changes in vocal fold length and thickness and vibration patterns, registration is also largely an acoustical event. The passaggi represent the muscular shifts, but they are not necessarily linked to the acoustical shifts that also take place. These acoustical shifts are affected by the vowel being sung; more specifically, by the unique resonance frequencies within the vocal tract when it is shaped for the given vowel.
HARMONICS AND FORMANTS
Just a quick lesson: The vocal folds produce a complex tone consisting of several harmonics - a fundamental frequency (which we perceive as pitch) along with several overtones. The fundamental frequency is also considered a harmonic - the first, or H1. (It is also called F0.) The next harmonic above H1 is labelled H2, and so forth. The overtones (H2 and above) are integer (whole number) multiples of the fundamental frequency. The frequency of H2 is twice the frequency of H1. This means that if the singer is vocalizing on A4 (440 Hz), H2 is at A5 (880 Hz), H3 is at E6 (1320 Hz), H4 is at A6 (1760 Hz), etc..
Because the vocal tract is not uniform in shape - it consists of bends and 'nooks and crannies,' and has a possible side (second) 'branch' (the nasal cavity) - it possesses several frequencies of its own. These tract frequencies are called formants, and they are created and altered by the shaping of the resonating cavities (e.g., through articulation of the various phonemes in a given language). Like the harmonics, they are numbered according to their frequencies. F1 and F2 are most relevant to vowel differentiation, while F3 and above are pertinent to timbre. We have more control over F1 and F2 because they are determined by the positions and shapes of the tongue, jaw, and lips. (Lengthening/shortening the vocal tract through lowering/raising the larynx and/or lip protrusion/retraction of the corners of the mouth also uniformly lowers/raises all formants.)
Why is all this relevant? (I know, singers are artists not academics. Who really wants to think about all this complicated science stuff, right? Why can't we just sing from our hearts and let whatever comes out of our mouths be enough?) Because many of the problems that singers encounter in the passaggio area (with regard to registration and resonance instabilities) are caused by resonance imbalances - by a 'clashing' of the harmonics of the sung pitch and the resonance frequencies of the vowel (formants). Furthermore, oftentimes the weakness or lack of power of the head voice is the result of harmonics falling outside resonance regions; of a failure to tune formants to harmonics so that they can receive an acoustic boost.
Again, successful registration is not purely a matter of physiological adjustment. It is also largely a matter of resonance. When this is understood, the singer will be inspired to find optimal adjustments of the resonator tract in order to accommodate the higher pitches - adjustments that will improve ease of production, beauty of tone, and mechanical efficiency, provide a stronger acoustic signal (more power, greater carrying capacity), and yield balance throughout the vocal system. Understanding the impact of resonance factors on vocal registration is imperative.
FIRST FORMANT VALUES
When singing in classical styles, the important harmonics lie ABOVE the first formant (F1) value for each vowel. This means that the higher harmonics (H2 and above) are permitted/encouraged to rise above the normal value of F1 for the given vowel and thus tune to a higher formant (F2 and higher). The singer will assist this process by stabilizing the length of the resonator tube (e.g., maintaining a comfortably low larynx), thereby stabilizing or even lowering F1. The resultant sound is head voice (if other aspects of coordination, including breath and glottal compression, are also in place) with a 'covered' tone (darkened vowels). This passing of H2 above F1 (which is accompanied by changes in the vowel - passive and/or active vowel modifications) is often referred to as a 'turning over' of the vowel or voice.
When singing contemporary commercial music (CCM), the important harmonics lie BELOW the first formant, as a general rule. As the harmonics of the voice source (vocal fold vibration) rise along with the phonation frequency (pitch), the singer makes choices about how he/she will deal with this formant. Typically, the CCM singer will continually raise F1 by altering his/her vocal tract (e.g., shortening it through laryngeal elevation, jaw lowering, lips spreading/retraction, etc.) and manipulating the vowel (e.g., 'leaning' or 'shading' the vowel toward another with a higher F1 value) so that the second harmonic never rises above it. The result is a 'mixed' voice or a belt, depending on certain other aspects of technique. The treatment of the formants depends entirely upon the singer's aesthetic goals, and there are pros and cons to each choice. To avoid being artistically or stylistically limited, it is beneficial for the singer to train the voice using both approaches.
The approximate first formant values for both males and females are listed below. (Females have slightly higher values due to their shorter vocal tracts.) Note that these are averages based on one study of speech (Hillenbrand, J., Getty, L.A., Clark, M.J., and Wheller, K., p.3103, J. Acoust. Soc. Am. 97(5), Pt.1, May 1995, p.3103). A bass may find that his first formant values are slightly lower while a high tenor may find that his values are the same as or higher than these average frequencies. Additionally, if the singer maintains a comfortably low larynx, as in operatic singing, the values are likely to be slightly lower than those of speech (neutral larynx position). Note, also, that I have rounded the average frequencies of the test subjects in this study either up or down to the nearest pitch, so they are not precise. The vowels are listed in order from lowest to highest F1 values for males.
Why is it important to be aware of these values (approximate pitches)? Because if the male singer understands that G5 (784 Hz), for example, is roughly his F1 value for the vowel [ɑ] and that when he is singing the note G4 (392 Hz), his second harmonic value is G5 (784 Hz), he'll understand both why his voice develops a very intense ring on that pitch (the juncture of F1 and H2), but nearly immediately loses it, or experiences 'weak' or powerless spots, as he moves up to the next couple steps in the scale. He'll also understand that this problem can be resolved quite readily by making some minor adjustments to the vocal tract to either stabilize (or lower) F1 or raise it, depending on his aesthetic and stylistic goals, and to facilitate an easier transition into the notes immediately above it and also ensure consistent 'power.'
Some vowels are more effective in certain tonal areas (registers) than others. Some vowels are more problematic in the higher register than in the lower register. When the singer knows his/her F1 values for given vowels, he/she will also understand why [i] and [u] seem to 'turn over' earlier or give him/her problems on certain pitches where the other vowels seem to present none. He/she will also understand why these same two vowels are useful in training classical head voice but not for 'chest mix' or belt (on account of their early turning over). Regardless of singing style, because of its comparatively high F1 value, [ɑ] is capable of greater consistency of intensity over a wider pitch range than [i] and [u]. If he/she is a CCM singer, he/she will understand why [ɑ], [æ], and [ɛ] are generally considered to be good 'mix' and belt vowels (on account of their high F1 values), and thus will shade all of his/her vowels toward one of these high F1 vowels when in the belt range. If the singer wishes to raise F1, he/she will subtly modify his/her speech vowels toward a neighbouring vowel with a higher F1 - he/she needs to know which one, though - thereby retaining the speech-like qualities heard in 'mixing' and belt.
For male singers (and probably for most female singers, as well), the first formant values increase in this order: [i], [u], [ɪ], [ʊ], [e], [o], [ɛ], [æ], [ʌ], [ɔ] then [ɑ]. Knowing this, the CCM singer needing to keep H2 below F1 by raising F1 can use this order to his/her advantage by subtly shading the vowels the vocal phrase toward the next vowels with higher F1 value. It isn't necessary, per se, to know precisely where each vowel 'turns over,' but an experienced singer who takes the time to really understand his/her voice through sensation and listening, will tend to feel and hear these subtle changes as they take place. If he/she understands what these acoustic shifts mean and what is happening, he/she will maintain dynamic registration and resonance by making the adjustments necessary to find a more suitable vowel for the given pitch.
The classical singer will tune his/her higher formants to his/her higher harmonics above the F1/H2 junction, and knowing the frequencies of F2 is also important to avoid having harmonics falling between formants and therefore not receiving an acoustic boost. However, due to the (unanticipated) length of this article, I'm not going to get into the topic of F2 tuning, which is critical to the passaggio and to head voice. Suffice it to say, for now, that as the higher harmonics rise above F1, they will begin to tune (with some assistance from stabilization of laryngeal height and passive vowel modification) to F2, F3, etc.. At certain points along the scale on certain vowels, more than one harmonic may be simultaneously amplified by higher formants, as well.
Adjusting tract resonances alone are not sufficient to produce a strong head voice. There are other factors, including breath management (discussed later in this article) and glottal adduction that must all come together. However, vowel modification is a good place to start, as it can make it more possible to transition successfully into the upper register. From there, other aspects of technique can be 'tweaked' in order to produce a fuller, more powerful sound in the upper range.
VOWEL MODIFICATION EXERCISES
Alternating between front vowels (to facilitate an early 'turning over' of the vowel and production of classical head voice) and back vowels in arpeggiated patterns are good exercises for some singers. In the following two exercises, the singer switches between the front vowel [e] (as in 'day') and the back vowel [ɔ] ('aw'). As the singer moves upward in key with each exercise, the modifications can be made earlier in the scale/arpeggio so that they are suitable for the pitch, vowel, and the individual's F1 value for the particular vowel. The singer must feel and listen in order to sense and anticipate the necessity of these alterations. The larynx should assume a comfortably low position (not high, but also not forced downward, especially by applying tongue root pressure) and the vowels 'rounded' and 'darkened' if the singer is to make the transition into head voice, rather than maintain a (CCM) 'mix' quality or begin to get shouty ('open timbre').
Exercise 3: [e-e-e-e-e-e-e] on 1-3-5-8-5-3-1 followed by [e-e-e-e-ɔ-ɔ-ɔ-ɔ] on 1-3-5-8-8-5-3-1 then [ɔ-ɔ-ɔ-ɔ-ɔ-ɔ-ɔ] on 1-3-5-8-5-3-1
Exercise 4: [e-e-ɔ-ɔ-e-e-ɔ-ɔ-e-e-ɔ-ɔ-e] on 1-3-5-8-10-8-10-8-10-8-5-3-1
Neutral vowels - [ʌ] (stressed schwa, as in 'but' and 'love') and [ʊ] (as in 'good book') - are often useful through the passaggio, and are very good vowels to start with because they represent the 'central' position of the vocal tract (its natural 'predisposition,' so to speak). From this neutral 'home base' (headquarters), very little adjustment is needed to create any of the other vowels. When the tube length is stabilized through the passaggio, these neutral vowels can very often be heard in 'behind' (i.e., in the pharyngeal space) all the vowels being articulated with the tongue, jaw, and lips - it becomes their 'common factor.' (I am not suggesting that singers should replace all other vowels with just these modifications - the 'omnivowel.' The neutral vowels simply result from a common pharyngeal dimension.)
Exercise 5: [ɑ-ɑ-ɑ-ʌ-ʌ-ʌ-ʊ-ʊ] on 1-2-3-4-5-6-7-8 then the reverse
Place these vowel changes around the primo and secondo passaggi. Think 'deeper' into the vowel as you ascend and with each modification so that the larynx does not rise and can pivot. Allow the vocal folds to thin and the voice to lighten as pitch ascends.
Exercise 6: [i-i-i-ɪ-ɪ-ɪ-e-e-ɛ] on 1-2-3-4-5-6-7-8-9 (then the reverse)
Note that, although these vowel changes are abrupt in these exercises, the process of vowel modification is, ideally, more subtle. The original vowel gradually transitions into the next modification over the course of several notes - they 'shade' chromatically - yielding intermediate vowels between them.
Mixed vowels and umlauted vowels are also useful for equalizing the scale. In mixed vowels, the tongue is saying one vowel while the lips are saying another. For example, the vowel [y] - found in the French word 'tu' and the German word 'für' - mixes the high tongue position of [i] with the rounded, pursed lips of [u], hence combining front and back vowel phonetic aspects. This means that some of the acoustic strength of both the front and back vowel series is incorporated within these vowels.
Exercise 7: [i-i-y-y-u-u-ʊ-ʊ] on 1-2-3-4-5-6-7-8 then the reverse
There are many 'mixed' voice exercises that can be applied to the range above the F1/H2 junction of each given vowel, but I'm just going to include two here for the sake of time and space:
Exercise 8: [wæ-wæ-wæ-wæ-wæ] on 1-3-5-3-1
This 'wa' (like a baby's cry) should be bright (twangy). Remain very speech-like as you ascend and delay the turning over of the vowel by lowering the jaw further and allowing more of the teeth to show (retracting the lips) without introducing tensions or stiffness.
Exercise 9: [me-e-e-e-e-e-e-e-e-e-e] on 1-3-5-8-5-8-5-8-5-3-1
Begin this exercise low enough in the range that [e] is easy to sing in a TA dominant sound without any obvious changes needing to be made to the vowel. Smoothly glide between the 8 and 5 to avoid abrupt changes to the vocal tract. As you approach the approximate location of F1 for [e] - you'll know by how it begins to sound, and it will probably start to feel unstable at the semitone above it if you haven't made any adjustments to the vocal tract - start to 'shade' the vowel toward [ɛ] then soon after that toward [æ]. As you ascend higher, lower the jaw further and allow more of the teeth to show (retract the lips). Although you'll notice your 'support' muscles working harder, don't push with the breath or 'dig into' the sound, as this will keep you stuck in pure TA dominance rather than a mix (which allows some gradual thinning of the vocal folds as pitch ascends). You'll notice that this exercise is more challenging to sing than Exercise 8 because [e] has a lower F1 value than [æ].
As I wrote earlier, there is no single way to train vocalists in the upper range, and not all exercises will work for all singers because they have differing aesthetic goals and slightly different vocal tract dimension and articulation habits. I can't possibly share every exercise or training approach here. (As you can see, there is much to discuss, and we've only just grazed the surface!) There are some who respond well to specific modifications as 'target' vowels (e.g., vowel charts), while others respond better by thinking in terms of vowel colour or timbre, while others still succeed with instructions for specific adjustments of the various components of the vocal tract (jaw, lips, tongue, larynx, pharynx, soft palate, etc.). The singer may find that, based on what he/she knows about his/her own voice and his/her vowel formants, he/she is able to create his/her own training exercises to suit his/her unique training needs.
BALANCING BREATH PRESSURE AND GLOTTAL COMPRESSION
It's impossible to discuss breath management in isolation, as there is an important interrelationship between it and the behaviour of the glottis/vocal folds, as well as with that of the supraglottal vocal tract, as the scale ascends. This interrelationship is more complex than can be explained here, but I'm nevertheless going to attempt to touch on some of the main aspects of it. It's also a little bit of a challenge to discuss breath management because, just as I believe that there is no ONE way to train head voice for all singers, there is also no ONE breath management technique or strategy that works for all singers for all parts of their ranges, all dynamics, and all singing tasks. This topic tends to elicit strong feelings of disagreement amongst 'rival style camps,' with CCM teachers and classical teachers vehemently disagreeing because their own 'support' needs and those of their students differ greatly. (Skilled 'hybrid' singers experience these differences firsthand.) There are, however, certain principles to which the singer would be wise to adhere. This discussion pertains to head voice rather than 'mixed' voice or belt, which demand different 'support' strategies.
Two common breath management errors made by male singers in the upper chest, middle, and lower head range involve 1) a pushing of the breath in response to, and in order to sustain, improper ('static') muscular and resonance adjustments, and 2) a 'pulling back' (so that 'support' is abruptly collapsed and glottal compression is abruptly released) in an instinctive reaction to mounting subglottic pressures or to facilitate a 'switch' into the 'lighter mechanism.' (This usually happens at the muscular shift or at the point at which F1 can be raised no further.) In other singers, there is a tendency to throttle the sound and impede breath flow by introducing constrictions, excessive glottal compression, and faulty tongue postures, but I'm going to focus on the first two today.
PUSHING OF THE BREATH
This habit is greatly influenced by the current teachings on 'diaphragmatic breathing' that encourage an exaggerated and entirely forward expansion of the abdominal wall upon inhalation followed by a forceful thrusting inward and upward of the abdominal wall at the onset of sound. This action, in turn, forces the diaphragm up quickly and generates tremendous subglottal pressure. When subglottal pressures are excessive, and especially when they are raised abruptly, the vocal folds generally respond in one of two ways: 1) they press together more firmly (often to the point of hyperfunction) in order to match their resistance efforts to the subglottal pressure; or 2) they 'buckle' under the high pressure and are blown apart, causing an airy falsetto sound.
Many teachers (e.g., Richard Miller) believe that there should be an increase in breath energy as pitch ascends. However, this concept is often misunderstood to mean that subglottal pressures are to be continuously raised in the ascending scale. Miller explains that the singer "increases energy but not volume" (Solutions for Singers, p.23). This 'increase in breath energy' refers to the need for the resistance efforts of the vocal folds to the exiting air to increase as they grow thinner and tauter with ascending pitch - they have to work harder because they are thinner - not to maintaining a thick vocal fold production and continuously raising subglottal pressures, which leads to escalating levels of loudness with rising pitch. The result of raising tensions and subglottal pressure is not a powerful head voice, though. It is a voice that gets stuck in the coordination used for lower pitches, and as a result, sounds shouty and unmusical and is unable to vocalize in piano dynamic (especially without adding air to the tone) because there is imbalance at the physiological and acoustical levels. The larynx is also usually forced high. This increase in subglottal breath pressure tends to prevent a gradual thinning of the vocal folds as pitch rises.
'PULLING BACK' WITH THE BREATH
As muscular tensions begin to mount in the upper chest register and then through the zona di passaggio, the singer (especially the singer who tends to 'muscle' his/her way up the scale, but also the dramatic or robust voice) may instinctually seek to release the rising tensions abruptly around the upper passaggio. To assist the muscular shift at this point, he/she may suddenly slacken his/her 'support' efforts, collapsing appoggio; that is, he/she loses the counter tension provided by the inspiratory musculature. When singers back off too much with the breath pressure (and by consequence glottal compression) like this, the voice flips into falsetto - with insufficient glottal closure and a CT dominant production in which the TAs are inactive, (thereby reducing medial compression of the vocal folds).
It is very common for singers to misunderstand what head voice truly is. Oftentimes, they think of head voice as being a light and bright sound. They may think of it as simply being any sound in the upper range that isn't 'chest' voice. However, a listen to great tenors like Pavarotti will reveal that head voice, when skillfully produced, can be quite loud and powerful. In fact, because operatic tenors' voices are often so powerful, many assume that these vocalists are still singing in chest voice. It is true that many modern operatic tenors sing with a long closed quotient of the vocal folds (and therefore a fair bit of TA engagement) up to about B4/C5, yielding a 'beefier' sound. (I realize that not all singers wish to produce a head voice sound like that of an opera singer, with a low larynx and darkened, rounded vowels, but this is a good example of the strength that can be achieved when there is balance of breath pressure, glottal compression, and resonance tuning.) If the singer maintains a steadiness and evenness of breath pressure as he/she transverses the passaggio, the voice's resonance will tend to tune appropriately.
BALANCE
Healthy, skillful singing technique requires a balancing of subglottal pressures and essential tensions: Too much breath pressure with too little glottal compression, and the vocal folds will 'blow apart,' while too little breath pressure with too much glottal compression will result in a tight, squeezed, overly compressed, choked sound. (For healthy vocal production, air needs to move through the glottis at an appropriate pace and amount.) The inspiratory hold (appoggio) assists the singer in achieving this optimal balance. 'Holding back' of the breath pressure must be done with the 'support' musculature, not with the glottis. The delicate vocal folds are not designed to resist tremendously high subglottal pressures and will not respond appropriately or healthily to them. This is why we must balance out these pressure from lower in the body - by balancing out the counter tensions between the expiratory and inspiratory musculature. If appoggio is maintained - that is, the inspiratory hold, in which the rise of the diaphragm is slowed by maintenance of the lateral expansion around the lower ribs throughout most of the sung phrase or the sustained note, along with an elevated sternum - an 'increase in breath energy' in the higher range will not place more pressure on the delicate folds than they can handle safely and musically.
Additionally, when breath pressures are balanced and vowels are permitted to alter as necessary for the pitch, the larynx will almost always be coaxed automatically into a comfortably low and stable (but not inflexible) position. There is no need to artificially darken vowels, force the larynx low using the tongue root, or to consciously manipulate the position of the larynx. Doing any of these things will produce an overly dark, dull sound and may prohibit laryngeal flexibility.
DYNAMIC APPROACH TO THE SCALE
While the supraglottal vocal tract is making adjustments for pitch (i.e., vowel modification), the larynx is making its own set of adjustments (i.e., the vocal folds are thinning thanks to increasing activation of the CT muscles and the thyroid cartilage is tilting/pivoting/rocking for head voice or the cricoid cartilage for 'chest mix' and belt), and the 'support' mechanism is also having to make some adjustments in response to these changes. (All of these adjustments tie into the 'aggiustamento' principles taught in the bel canto tradition.) These flexible adjustments cannot be made in isolation, or apart from also making adjustments in other parts of the vocal tract or in the singer's technique without a loss of balance. How does the singer coordinate these? Through years of (the right kind of) focused practice. He/she must develop a strong kinaethetic sense, as well as good functional hearing (the ability to aurally discern what is happening on a functional level) and the ability (fine motor control) to 'fine tune' his/her coordination.
Subtlety of adjustment is critical. If subglottal pressures are permitted to remain relatively constant (except, of course, where they are permitted to rise and fall for artistic effect - dynamics) beginning BEFORE the primo passaggio (before the point where they begin to rise in the upper chest register) and crossing through the secondo passaggio, and if flexibility of adjustment of the vocal tract is simultaneously encouraged, the transition from chest voice to middle voice to head voice will be smooth and seamless, and head voice itself will be 'supported,' strong, balanced in resonance, and beautiful. If any one of these elements falls out of balance or remains static, however, head voice will be either improbable or poorly produced. Anticipation and preparation are key. The singer must anticipate changing physical coordinations and changing relationships between pitch (harmonics) and resonance (formants) and prepare for them in advance, before the instrument starts to fall out of balance (e.g., unintended increases in loudness, register breaks, etc.), by making graduated adjustments. While it's exciting to let the voice build and to soar in the higher range, most vocal exercises (scales, arpeggios, sirens, etc.) should be practised with no noticeable increases in or loss of power (loudness) as pitch ascends. This evenness prevents the voice from becoming locked into or stuck in the coordination that pertains to the lower part of the range.
Earlier in this article, I wrote about the two passaggi. One of the greatest inhibitors of flexible adjustment in the scale is thinking that the voice has only one point in the scale at which it 'switches gears' or changes registers - THE passaggio, or THE 'break' - and thus only two registers. Typically, this one pitch is around E4/F4/F#4 for both male and female classical singers or the 'break' for CCM singers, (E4/F4/F#4 for males and A4/Bb4/B4 for females), which usually occurs several notes above the first muscular shift in females and the second in males. If all adjustments are delayed until the secondo passaggio or even a few notes above it - if the singer maintains the same coordination as high up as possible then 'bridges late' - the change of registration will likely be abrupt. Loudness will gradually increase through the upper chest range and the zona di passaggio, and then the voice will experience a sudden and noticeable shift into the 'lighter mechanism' unless other adjustments are made (e.g. raising F1 through narrowing and shortening the vocal tract). Instead, the singer needs to anticipate and develop greater awareness of the incremental adjustments that take place throughout the scale and 'bridge early' (mainly a matter of resonance adjustment here) so that a proper middle voice (classical) or a 'mix' (CCM) that doesn't sound shouty or otherwise imbalanced can be achieved. (Again, this earlier transition is pertinent to head voice in the classical sense, but not suitable to most CCM, as it will not encourage a 'mixed' voice production that is desirable in most commercial styles of singing.) A consistent subglottal pressure will assist this transition and help maintain balance.
On every note in the scale, there is a slightly different muscular, resonance, and breath pressure balance. Some refer to this balance as 'placement,' stating that there is naturally a different 'placement' on every note of the scale. (Some have gone so far as to call each note within the scale a different register unto itself!) The singer needs to find this 'placement' by balancing out individual notes first, then by balancing out a few notes in succession, and then finally lengthening the sung pattern. He/she must find the correct vowel for the pitch, which will help him/her find the correct muscular and breath balance. Although this work may be tedious, merely singing entire scales repeatedly will likely not help the singer experience these chromatic shifts.
Exercise 10: Mastering the Passaggio by Semitones
Sing [i] or [u] on a note in the middle range, roughly between the two passaggi for males (e.g., C#4 for a baritone, D#4/E4 for a tenor) and around the lower passaggio (E4/F4/F#4) for females. This note will be called the 'home (base).' Find the right vowel 'shading' (modification) for this note. Keep the larynx stable and comfortably low, and the breath steady - neither pushing nor pulling back. Aim for a warm, rounded sound and keep the mouth space moderately small, especially on [i]. While sustaining this note, slowly slide down a half step. Don't think 'down' or mentally conceive of the note as being very different from the note just a half step higher, or else the mechanical and acoustical adjustments will be conspicuous. Note the slight adjustment that is needed in order to maintain balance. Take a breath. Now, return to the 'home' note. While sustaining it, slowly slide up a half step, taking note of the subtle adjustments needed, then slide back down the half step. Now, starting on the 'home' note again, slowly slide down the half step then back to home then up the half step and then back to home. Gradually grow this range of balanced notes by semitones in both directions.
BREATH MANAGEMENT EXERCISES
The following exercises are designed to encourage a slowing down of the rise of the diaphragm in order to keep subglottal pressures at sustainable, healthy levels, even for loud singing and within the higher range. This 'inspiratory hold' (appoggio) will assist a smoother transition into the head register, as it will encourage muscular and resonance balance (by stabilizing the position of the larynx and allowing for flexible resonance adjustments throughout the passaggi and upper register). The inspiratory hold will also assist the singer in conserving his/her air so that he/she will be able to sustain notes for longer and sing longer vocal phrases without running out of breath.
Exercise 11: The Farinelli Exercise
In this traditional exercise - it's 'an oldie but a goodie' - the breath cycle is divided into three phases: 1) inhalation; 2) suspension/retention of the air; and 3) exhalation. Inspiration and expiration are evenly paced over a given count so that the singer goes from 'empty' to 'full' (and then the reverse) over an even count. Traditionally, the singer paces inhalation for 4 beats/counts/seconds - I prefer using seconds or a metronome in order to ensure accuracy of pace and to track progress. The singer should not get the sense that the air is filling up his/her throat - which means that he/she has taken in too much air - as this will prompt the glottalic valving system and the epiglottis to activate and try to cap off the air and the throat will 'close.' Then, he/she suspends his/her breath cycle by putting his/her inspiratory posture 'on pause' for 4 counts. The glottis remains open, as does the mouth (to ensure that the breath is not being held back by them but by the inspiratory musculature), but no air moves into or out of the lungs during this phase because there is no muscle acting on the diaphragm or lungs to prompt a change in pressure. In the third phase, expiration is evenly paced over 4 counts, and the diaphragm is allowed to rise - not pushed upwards, but 'allowed' - and thus the lower ribs (but not the sternum) to move back inwards in preparation for the next breath cycle. In the very next breath cycle, the singer performs each phase over a count of 5 counts for each cycle. With each subsequent breath cycle, another count is added to each phase until the singer reaches his/her maximum length of breath cycle: 6-7 seconds per phase is pretty common for newer singers. Then, he/she makes his/her way back down in count until he/she has returned to 4-4-4. This exercise should be practised a few times a day. While silent breathing exercises alone will not fully train breath management skills, the Farinelli exercises is useful for helping develop the coordination and the strength needed to slow down the rise of the diaphragm during phonatory tasks and for reshaping the singer's thinking about how he/she should breathe for singing.
Exercises 12-14: Semi-occluded Phonations
Building on the same coordination of the Farinelli Exercise, the singer can add semi-occluded sounds, including [ŋ] (NG), [m], [n], [z], and [v] to help slow down the exiting air while encouraging efficiency of vocal fold vibration.
[s-z-s] (4-8 counts for each phoneme/sound). The hissing should be strong and 'supported.' There should be more tone than air heard in the [z]. The collapse of the lower ribs should be delayed until perhaps the end of the [z]. Then, the return to the pre-inspiratory position can be controlled gradually until the end of the second [s]. 'Leftover' air can be expelled silently after the final [s] has been released.
[s-z-o-z-s] (for 4-6 count each). The goal is the same as that of the previous exercise. The singer should practise slowing the collapse of the ribs until about 1/2 to 2/3 of the way through the exercise. This should be sung on several pitches at different places in the scale so that the singer can feel the differences in the lower body engagement that are activated at different pitches. The hissing of the [s] should be strong, as should the buzzing of the [z]. The breath pressure should remain even during the production of the [o]. If the singer, instead, thinks of the vowel as requiring stronger pressure than the [z], the vowel will blast more loudly and the pitch will rise. (The pitch should remain the same for all voiced sounds in the exercise.)
1-2-3-4-5-6-7-8-7-6-5-8-7-6-5-8-7-6-5-4-3-2-1 on [z] or [v]. This exercise is to be performed rapidly with an effort to maintain the inspiratory hold throughout at least half of it (or for as long as is both possible and comfortable). The singer should avoid 'revving' (increasing loudness) on the higher pitches by pushing more breath pressure. There should be no noticeable increase in 'power' on the higher notes. The larynx should remain in a stable, comfortably low to neutral position.
Exercise 15: Lying Prone (Face Down)
With hands on top of each other and palms facing downward on the floor, the singer lies on his/her abdomen and places his/her forehead on his/her hands. (This position allows the singer some space between his/her mouth and the floor, but does not represent optimal posture of the cervical spine as the head would be too far back in relation to the torso.) While in this position, the singer hums (or uses any other semi-occluded sound) a scale or song in an energized manner. He/she takes note of how his/her muscles are engaging, and which ones are involved in support. He/she should continue to resist the early collapse of the inspiratory posture. Because the abdominal wall is prevented from distending/stretching/protruding forward (on account of it being pressed against an immovable floor), this position is ideal for training a more lateral expansion, including an expansion of the lower ribs in the back. This will allow for a deeper breath because the diaphragm will be permitted to lower more than it would if there were too much forward expansion with consequently limited sideways expansion. (When expansion is only forward in the abdominal wall, the lower ribs can be seen to narrow - move inwards - which means that the thoracic cavity is only expanding vertically, not horizontally, thereby limiting its potential volume. It also means that the diaphragm is not lowering as much.)
Exercise 16: Sirening
This exercise is not specific to breath management, and any exercise can be used to help improve breath management skills if the focus remains on the inspiratory hold. I'm using sirens because they are one of the types of patterns in which singers tend to 'rev' or push too much breath pressure as pitch ascends, which can lead to a locking up of the support mechanism and a shutting down of the throat.
First, as an experiment, spanning the passaggio area, sing 3-1-5-3-8-1 sliding between notes while forcing/thrusting the abdominal wall inward with each of the higher notes. Very likely, the voice will not only 'rev' (be louder and more pushed sounding) on the higher notes, but it will also break or become unstable. Now, sing the same exercise, sliding between notes smoothly and in a controlled manner and taking special care to avoid 'revving' the higher notes. Instead, on the higher notes, think about maintaining the expansion of the lower ribs (e.g., phase 2 of the Farinelli Exercise) - some singers like to think 'out' (sideways, not forward) or 'down' for their support, but don't take this concept to any extremes. There should be no jerky movements of the 'support' mechanism. While you may feel a bit more abdominal wall engagement (likely the transverse and oblique muscles) on the higher pitches, the actions should be subtle and controlled - prevented from being forceful or abrupt. If you have achieved greater balance of the entire voice system this second time singing the exercise, the higher notes in the pattern should still be strong and powerful, but not 'blasted' and breaking, and you should have more air in reserve. The tone should also be warmer because the steadier and more consistent subglottal pressures have helped the larynx to remain stable and low.
Exercise 17:
[si-i-i-i-i-i-o-o-o-o-o-o-ɑ-ɑ-ɑ-ɑ-ɑ-ɑ-ɑ] on 1-3-5-4-3-2-1-3-5-4-3-2-1-3-5-4-3-2-1. Like the previous exercise, the focus should be on maintaining the lateral expansion on the higher notes in the pattern (e.g., not 'revving'). As the singer moves higher in the scale, the larynx should remain stable and the vowel should be permitted to adapt to the pitch.
Exercise 18:
[ti-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i-i] on 1-1-2-3-3-4-5-5-6-7-8-9-10-11-11-10-9-9-8-7-7-6-5-4-3-2-1. (This is a tough exercise to explain without the benefit of it being written properly on a staff. There are 1/8 note rests between each number that is repeated, e.g., between 1 and 1.) With every rest, the singer does a quick 'check' of his/her support to ensure that he/she has not allowed the lower ribs to collapse prematurely. He/she should be thinking of the suspension coordination achieved in the second phase of the Farinelli Exercise. During the rests, the glottis and mouth are open, but there is no movement of air either into or out of the body. If the singer gets an adequately low breath to begin with and then conserves his/her air (without compromising vocal power - which is also a matter of resonance, not just of breath pressure), he/she should be able to sing this pattern on a single breath. If not, the rests allow for partial breath renewals ('sips'). Early on, it might be necessary to include a longer rest at the top of the scale (between the first and second 11 notes) for a fuller breath renewal. The [i] vowel is used here because it encourages an earlier 'turning over' into F2 tuning (e.g., head voice). However, other vowels should also be practised.
MAINTAINING THE 'OPEN THROAT' IN THE UPPER REGISTER
To properly prepare the vocal tract for phonating, the singer must achieve quiet, deep inhalation in which the soft palate elevates, the pharynx dilates, and the larynx lowers naturally and comfortably. Some describe this posture as the feeling of the 'incipient' yawn (the beginning of a yawn, but not taken to the extreme of a full yawn, which would flatten the tongue and depress the larynx, making for a falsely darkened sound). So long as the singer doesn't suffer from extreme hyperfunction and tensions, this vocal tract set up is easy enough to achieve. Maintaining it during the sung note or phrase, however, is more challenging. Many singers have tendencies to push and/or to squeeze in the upper range. The squeeze reflex is greatly influenced by the singer's thoughts and feelings about singing higher notes (e.g., fear of cracking or 'breaking,' not liking his/her tone in the upper register, etc.). It's described as a reflex because after a while, the body develops muscle memory, and so every time the singer prepares to sing a given note or within a given part of the range, his/her muscles automatically behave in the manner in which they were trained to. This behaviour will continually be reinforced, and this squeeze reflex will become stronger, until the singer consciously makes changes. The squeeze reflex is ultimately eliminated through proper set-up of the vocal tract (part of pre-phonatory tuning), finding a better balance of subglottal breath pressures and glottal closure at the onset of sound, and growing in confidence through technical security.
Mental imagery (that is clear and does not impeded natural function) is often a useful tool for helping to reshape the singer's attitude toward singing high notes. Concepts such as 'inhalare la voce' (to 'inhale the voice') are helpful. Instead of merely preparing the vocal tract, then almost immediately activating the pushing or squeezing reflexes, the singer thinks of the voice as 'coming into' him/her, rather than being pushed out of him/her. He/she maintains the feeling (and thus posture) of deep inhalation throughout the sung phrase, which prevents the throat from 'closing.'
Thinking of (mentally envisioning) pitch as a horizontal (rather than vertical) phenomenon is often beneficial, as well. When the singer thinks 'up,' the larynx tends to follow suit, as do the shoulders, chin, and parts of the face (e.g., the corners of the mouth retract, the eyebrows rise, etc.). I find the thinking 'down' as pitch ascends eliminates these kinds of movements choreographed to pitch and encourages a natural depth of vowel and an opening of the authentic resonating space. Some singers gesture downward with their hands, while others slightly bend their knees with higher pitch to counter the tendency to raise everything along with pitch. I always like to envision the voice as a line in front of the face that smoothly arcs downward as I slide up in pitch.
The traditional definition of the 'open throat' entails a comfortably low larynx, a dilated (wide) pharynx (which implies a higher, more fronted tongue posture than typically occurs in speech), and an elevated soft palate (which tends to yield a more characteristically classical timbre). The following exercises are going to target development and maintenance of this posture - what Ingo Titze calls a convergent resonator shape, or inverted megaphone shape. Remember that because CCM singers tend to raise F1 through laryngeal elevation and pharyngeal narrowing, as well as by lowering the jaw and retracting the corners of the mouth - this fact is supported by numerous studies by scientists, including Ingo Titze and Johan Sundberg, as well as by voice researchers and teachers such as Kenneth Bozeman and Donald G. Miller - the divergent resonator shape or 'megaphone' resonator shape (characteristically CCM vocal tract posture) does not represent an 'open throat' by this traditional definition. There is, of course, a significant difference between 'narrowed' and 'constricted.' Skillful CCM singing allows for a narrowing of the throat (pharynx) and rising of the larynx that do not lead to sensations of narrowness or constriction. The throat feels relatively 'open' and free of unnecessary tensions.
Exercise 19: Deep Inhalation
Practising deep, quiet inhalation is a way to silently train the vocal tract to respond to reshaping. Breathing through the nose will encourage the tongue to remain higher - resting along the anterior pharyngeal wall and lining the hard palate - and will also warm, moisten, and filter the air before it reaches the vocal tract and lungs. However, inhalation through the mouth encourages a better stretch of the soft palate (which is necessarily down during nose breathing to open the velopharyngeal port). I've seen this silent inhalation practice work very effectively for singers with low soft palate issues, as it gradually releases the tensor muscles that prevent the soft palate from 'doming' properly.
Exercise 20 (Classical Head Voice): [u]-slide-[u] on 1-slide-3-slide-1
Beginning below the lower passaggio (perhaps E3 for males and D4 for females), the singer begins with a deep, 'open-throated' inhalation and mentally prepares for a warm [u] vowel as it forms in the throat. As he/she begins to sing the exercise, he/she must resist the desire to push his/her voice out, thereby closing the throat. He/she establishes a warm, rounded, balanced [u] on the root note (1), then slides to the third (3) without allowing the vowel to thin or brighten, then back down to the root note. The warmth, roundedness, and depth of the vowel comes from the open resonance space, not from falsely darkening the timbre (especially through depression of the larynx by employing the tongue root). This exercise helps maintain a low, stable larynx by allowing the thyroid cartilage to pivot/rock in the middle range, thus countering its tendency to want to rise and cause a narrowing of the pharynx. It's more beneficial to think in terms of maintaining a consistency of timbre from the root to the third than to focus on consciously manipulating the height of the larynx, which may lead to a depressed larynx and vocal strain.
This exercise also encourages an easier and earlier 'turning over' of the vowels because when the larynx remains stable and comfortably low, all the formants lower, and thus the vowels turn over slightly sooner. The [u] is also used because it 'turns over' early.) The singer will notice that as the vowel moves through its 'turning over' point, it starts to passively modify. The consistent laryngeal position and pharyngeal expansion tend to yield a neutral [ʌ] ('uh') or [ʊ] (as in 'good') in behind the vowel being sung with the tongue and lips (the original vowel).
Many singers find that they experience a bit of a 'tug of war' between the suprahyoid ('swallowing') muscles and the infrahyoid ('inhale') muscles that pull the larynx up and down, respectively. This will exhibit itself as a bit of instability in the sound as the weaker infrahyoids attempt to stabilize the larynx. Although disconcerting, this is normal and temporary, and is an encouraging sign that means a better balance is being achieved. In time, stability will come. However, if the squeezing and pushing reflexes are deeply entrained in the singer's technique and muscle memory, they will require a great deal of time and patience to eliminate. Don't reinforce the squeeze reflex by continuing to sing higher once it's activated. Instead, move back down in pitch and begin gradually growing the range in which you can maintain the depth of timbre and 'open throat.'
Note: Laryngeal height is individual and relative. Depending on the individual's anatomy, the larynx may be naturally positioned higher or lower in the neck. There are also varying degrees of 'low,' ranging from depressed to comfortably low to neutral (speech level/height). In terms of laryngeal height, 'acceptable' or 'desirable' is dependent upon the vocal situation. To determine what degree of 'low' is right, the singer must feel and listen.
Exercise 21 (Classical Head Voice): [u]-slide-[u-ɑ-e-i-o-u]-slide-[u] on 1-slide-3-3-3-3-3-3-slide-1
Once Exercise 20 can be performed with a consistency of timbre and laryngeal height, other vowels can be sung on the third of the scale. The singer should establish the warm, rounded [u] first, slide up on this [u], change vowels (without 'mouthing,' over articulating, or exaggerating the differences between the vowels) smoothly without losing the 'line' in the voice (consistent 'ring,' resonance balance, and airflow), then return to the [u] before sliding down on this vowel.
Exercise 22 (Classical Head Voice): Low Larynx Exercise 1-3-5-8-8-8-8-5-3-1 on 'buh,' 'guh' or 'mum'
Early in my teaching career, I was not a fan of the 'dopey,' low larynx exercises often prescribed to singing students because, (in addition to their producing 'ugly,' overly darkened sounds), in singers with very strong swallowing (laryngeal elevation or squeezing) reflexes, consciously forcing a habitually high larynx to remain low can easily lead to strain. In the tug-of-war between the strong, frequently used swallowing muscles and the weaker, infrequently used infrahyoid muscles - because we don't inhale as deeply during speech or at rest, the larynx doesn't lower as much - the suprahyoids will always win. They need to be gently and gradually deactivated during singing. That being said, for singers will only slight laryngeal elevation and without a tendency to 'muscle' and squeeze, low larynx exercises can be effective. (I do not recommend these kinds of exercises for singers with strong swallow reflexes.)
In contrast to how this exercise is usually performed, the singer should focus not on lowering the larynx and falsely darkening his/her timbre, but on achieving depth and roundedness in the vowel through maintaining the posture of the throat achieved at the time of deep inhalation. The singer must be very careful to ensure that he/she does not force the larynx down (depress it) with tongue flattening and/or retraction and/or narrowing. Before each repetition of the exercise, he/she should 'reset' his/her vocal tract with a deep, 'open-throated,' quiet preparatory inhalation - that is, he/she needs to 'recalibrate' the vocal tract at each breath renewal. Then, it might help for him/her to think about the concept of 'inhaling the voice' as he/she vocalizes to avoid pushing on the higher notes and activating the push reflex. As in Exercises 2 and 3, the vowel should be allowed to modify passively as the stable larynx stabilizes the position of the formants. If it modifies too soon, it may be a sign that the larynx is rising. Laryngeal height can be monitored by gently placing a two or three fingers on the thyroid cartilage (Adam's apple). The thyrohyoid space (the space between the Adam's apple and the hyoid bone) should not be loose and open, but also should not become smaller and stiff. Its size differs between individuals. However, any changes in its size could indicate residual tensions from activation of the swallowing muscles.
Stabilizing the larynx may take time. It will entail a study of breath management and vowel modification.