Sunday, May 20, 2012

Kashu-do (歌手道): "In the Mask": A Sometimes Evil Necessity!

My time with the late, Ada Finelli, in Italy taught me many things about the experience of learning and teaching to sing.  Among them is an axiom that I have come to coin: "Every superficial jargon is based on a more complete and fundamental principle of singing."  Why have so many singers advocated over the years that the voice should resonate "In the Mask"?  Yet, just as many have advocated the other side, that "placing" the voice in the mask is a recipe for tension and dysfunction.

Many of my friends in the voice science community will say that one cannot place the voice and that correct muscular postures and resonance adjustments produce sensations that perhaps each singer feels differently, given that each has a unique vocal mechanism. This is correct!

But equally correct is the traditional principle that singing is passed along by sensations and not by words alone. Demonstrating a concept for a student very often speaks more clearly than any explanation.  It depends on what point in the process the student is currently experiencing.  And therein lies the disconnect between science and tradition.

Vocal Science fails in one most fundamental way.  It does not truly follow the scientific process when it comes to the analysis of voices.  Up to this point, vocal science has not established a vocal ideal!  Norms have been established based on selected professional singers' voices that happen to be available for analysis, more often because they are academically bound and not usually doing battle with an operatic orchestra.  One can get away with a great deal in a small recital hall and a piano!

The sensation of Mask Resonance is not based on resonance of the sinuses.  Singers who do not understand the way resonance works will swear that the resonance is happening in this cavity or that! Science proves beyond a shadow of a doubt that the nasal cavity is not a resonator.  William Vennard's experiment, stuffing the sinuses with cotton and then milk, proved that there was no acoustical change when the nasal cavity was stuffed.  The experiment has been repeated by other scientists since and the result has always proven to be the same.  Still singers feel strong and specific vibrations in the bones of the head.  This is a principle called bone conduction.  Vocal tract vibrations are transferred through the skeleton in the form of vibrations in head and chest.  The specific nature of these vibrations are based upon the overtones produced by the oscillating vocal folds and the filtering of the vocal tract to emphasize certain areas of acoustic strength based upon the five identified strong acoustic bands called formants.

For a given pitch (frequency) there are three possible basic glottal (vocal fold) postures:  Too deep and breathy, appropriately deep and appropriately closed and shallow and pressed.  We seek a fold posture that is deep enough to create a spectrum rich in overtones both low and high and still allow for complete glottal closure without the frequency falling (singing flat).  This follows the principle that two variables influence the length of the glottal cycle (and therefore pitch accuracy), namely fold depth and fold closure (medial pressure).  Deeper folds take longer to close, given the pattern of the mucosal wave.  Likewise pressed folds take longer to open since the glottal squeeze works against the opening of the folds.

The strategy to achieving mask resonance (i.e. sensations that accompany a strong influence of the singer's formant) is first to create strong overtones and then chose a vocal tract adjustment (vowel) that gathers two of the top three formants closely on either side of a single strong harmonic, a principle called clustering of formants.

An exercise I use often to bring singers to this sensation (once the fold balance has been achieved over months of lip trill  and vocal fry exercises) is the following patterns:

Start on D3/D4 (male/female) on a clear, strong chest voice on [a], maintain the sensation of chest voice and without detachment, sing legato to D4/D5 (octave above) of [wi] and then descend on a five-note scale to G3/G4.  In otherwise 5-5-4-3-2-1 (two 5s constituting an octave) in G Major on [a-wi-i-i-i-i].  The exercise can then be taken further:  Still beginning of D3/D4, 1-8-7-6-5-4-3-2-1 in D Major following the pattern [a-wi-i-i-i-i-i-i-i].

The goal is to attempt to maintain the efficient phonation of the chest voice as the resonance of the [i] vowel emphasizes the narrow sensation of the epilaryngeal tube responsible for the resonance of the singers formant.  The chest tone guarantees a tone rich in overtones and the [i] vowel with its upper formants close to each other  would cluster around a harmonic in the 2800 range, the frequency of the singers formant.

In terms of sensation, this does two things for the singer: 1) Attempting to maintain the phonation sensation of the chest tone makes it clear that the tone needs to stay appropriately full and closed.  A jump of an octave guarantees that the vocal folds will thin out, but appropriately and without losing closure and produce a falsetto pattern as is often the case with women in the middle range.  2) The natural resonance of the [i] vowel (providing the glottal oscillation remains full and efficiently closing during the adduction part of the cycle) will bring the singer to the sensation of resonance in a narrower tube (the epilarynx), which by bone conduction is experienced in the mask (the bridge of the nose, between the eyes, etc).

Having established the sensation of the narrow resonance of the epilarynx, the singer can then vary the exercise to 1-8-7-6-5-4-3-2-1 on [a-wi/a-a-a-a-a-a-a-a], making the vowel change of the upper octave (8) and attempting to maintain the sensation of narrow resonance as felt of the [i] vowel.  The glottal source must continue to produce a rich spectrum of overtones and the choice of the specific [a] vowels should be guided by how strongly the singer can maintain the narrow resonance of the epilarynx as felt naturally on [i].

It is important to note that the Singer's Formant, carried by the epilarynx and to the mask by bone conduction only occurs when the source tone (the glottal vibration) produces strong overtones.  There is a trap that has ruined vocal balance that feels similarly to the correct resonance adjustment of the Singer's Formant.  In an attempt to "place" the voice in the mask before the fold posture has been achieved, some teachers will have a student sing a bright [i] vowel, whereby the larynx rises making it impossible to achieve the 6:1 ratio of pharynx to epilarynx that is necessary for the production of the Singer's Formant.  In those instances, the lower overtones are suppressed and the singer only experiences the high overtones that are available (usually weak).  Still, some singers, because they have a particularly large pharyngeal structure, can achieve the Singer's Formant even with a high larynx.  But those are not the norm.

It is my experience that when a singer works to develop a glottal posture that is appropriately full (deep, adequate chest content), then glottal closure can be efficient without too much medial pressure (pressing).  This also makes it possible to achieve excellent trans-glottal flow preventing the rising of the larynx.  Appropriate sub-glottal pressure is built during the closed part of the glottal cycle and the pressure is released during the slightly longer open phase when there is no excessive medial pressure.  Aside from the case of singers with large pharyngeal spaces conducive to the production of the Singer's Formant even when the glottal source is pressed, an appropriately deep glottal posture is necessary in order to create the conditions that make the Singer's Formant possible.  Only then can the experience of epilaryngeal resonance be carried via bone conduction to the mask.

In short, mask resonance is real and necessary and it is my belief that although we have singular vocal mechanisms, all voices function more or less the same way.  Mask resonance when based on correct principles of function can be reproduced and passed along. However, pressed voice with a raised larynx can produce an experience that is similar in sensation but is not efficient and could lead in a very short time to faulty and harmful vocal production.

© 05/20/2012

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