Monday, July 13, 2015

Kashu-do (歌手道): Race Fear in Opera: The Scary White Elephant in the Room

Who is afraid of the word Race in Opera?  Everybody!  I have never wanted to concentrate my thoughts on the subject of race in operatic casting because I thought it detracted from the necessity to concentrate on what one can do as opposed to what one has no control over.  When I think on the Black singers who have accomplished greatness in Opera, I see commonalities:  great voices combined with unlimited discipline and determination.  As a singer whose race would probably be considered in casting, it was clear to me that I could not change my race so why concentrate on it? I concentrated on what I could control. Edward Pierson II, was the first Black opera singer I knew. His wife was my first art teacher at Winfield Scott School No. 2 in Elizabeth, New Jersey in the United States.  Soon after my year in her class I became passionate about the game of tennis and joined a city  -sponsored summer youth tennis program.  There I met his son, Edward Pierson III, who played tennis and also sang with a beautiful tenor voice. We sang in a local chamber choir together the year after and after playing several tennis games with his father, the elder Ed Pierson, I learned that the older gentlemen with the Darth Vader voice was actually an opera singer who sang Hollander at New York City Opera among other great roles.  Mr. Pierson was kind and friendly and gentle.  His speaking voice, unforced resonated everywhere.  I was just beginning to come to grips with the fact that opera was my passion and having these role models was important.  Soon after Mr. Pierson, I met Simon Estes, George Shirley, Jessye Norman and Leontyne Price.  Their performances and their manner was always concentrated, musically impeccable and they without exception stressed work ethic, continual improvement, never taking your gifts for granted and never resting on your laurels! 

In a laudable and responsible approach, these great pioneers concentrated on what they could affect through hard work and never concentrated on complaining against racism.  It was tacitly understood that complaining would only bring retribution, so the best thing to do was simply to do the job as well as was possible.  I believe this attitude was passed down to the latter generation.  I know that I learned this from George Shirley, not in those specific words, but in is gentle demeanor and in the balanced and cool-headed way he approached everything.  Perhaps it was influenced by Martin Luther King and the ideology of non-violence that was the understood philosophy of the time.  I could never disrespect those heroes for their quiet perseverance.  It is what they had to do to help put Black faces on the operatic stage (their own) and thereby inspire the generations after them to go further.

There is also a very paradoxical problem in calling out racism in the operatic field.  I don't know a single Black singer who did not achieve his or her success without the support of White supporters, whether a patron who took real interest in them as artists and human beings, or a loving teacher, coach or conductor, or even the administrator of an Opera house.  So how do you call racism out in those situations without offending the very people who support your rise and help maintain your progress?

When I recently posted some questions on my Facebook page regarding racism in Opera, not a single one of my working minority friends responded to the questions and I have many--from those who work at top houses all over the world to those who work at mid-level houses in Europe and regional houses in the United States.  Considering the previous paragraph alone, I empathize with my colleagues' choice of just staying out of the conversation.  Additionally, as a friend, a non-performer, who is close to these singers expressed, these singers do not wish to be linked to any conversation on social media about Race in Opera for fear of losing their jobs or losing their status in the mainstream.

As another friend of mine mentioned on my Facebook feed, the Metropolitan Opera (It is only normal to target the MET, because it sets the standards for how regional opera companies in the U.S. behave) lists its soloists roster for 2015-2016 including 272 singers with only 8 Blacks (3%) and 11 Asians (4%).  The estimated percentage of Asians in the United States in 2015 is 4% while estimated percentage of Blacks in the United States is 13%.  Asians are represented at the Metropolitan, Blacks are severely underrepresented.  Yet equal representation is not the central question.  The central question is whether the disparity has to do with tacitly accepted racist practices that are not addressed because everyone is afraid to open what could be a very uncomfortable Pandora's Box.  Because the issue is so potentially volatile, no one within the Opera performing world is willing to address it.  Consequently racist elements may exercise their poisonous activities in the guise of artistic realism by saying that such a singer does not look like what these characters might look like historically, for instance.  A red-herring argument, as we have enough precedence to counter that posturing!

How then do we approach this issue?  As is evident by the activity on my Facebook page, my fair-minded White colleagues are not afraid to speak about this, because they do not fear retribution. Perhaps some do for merely raising the question!  The call to justice therefore is incumbent upon the Operatic establishment worldwide to make certain, once again that casting practices are not based on the composition of skin but rather on the content of character and the viability of the artistic talent.  Criteria in opera are many!  One singer can be dismissed because his diction is not perfect.  Then one goes to a performance to find that the singer who is cast is severely vocally inadequate.  When the singer dismissed for his diction is a Black or Asian singer, one must wonder if casting such a singer aside for diction is not simply a pretense for excluding a non-White singer.

Indeed operatic casting involves not only racism, but lookism of all kinds and homophobia.  One colleague of mine explained that a friend of his was told point blank that he was a superior artist but he could not be cast because those who make the decisions were afraid he would be too effeminate onstage.  An effeminate gay man can "butch it up" just as a heterosexual can easily play effeminate if they are good actors.  However, a Black man or an Asian woman cannot change their race.  That is what the make-up and costume crews are for: to help us transcend realism and get into a world of imagination.  The issue of blackface and racist American minstrelsy have made the question of make-up deferring to the character's race problematic.  Here we are putting the cart before the horse!  I would prefer to see us deal with the problem of getting Black singers on stage because they are talented enough and deal with the issue of stage make-up after.

Indeed there is a lot of responsibility to be shared.  What made the Verretts and Shirleys of the operatic world so beyond reproach was their exceptional musicianship and attention to details (linguistic, stylistic, stagecraft, physical fitness, etc).  These singers were beyond reproach on so many levels.  Singers of African decent must do their part to be as beyond reproach as one can be, such that nothing can be used against them.  The administrations of opera houses must make a point of making sure that their casting directors do not practice race-based biases, inappropriate lookism, etc.   This includes making operatic talent the main focus of their hiring policies and not nepotism with regards to their artistic leadership (i.e. conductors and directors).  Productions that require decisions on a racial line where race is not of fundamental concern to the operatic plot must be frowned upon. The journalistic media must become more objective with regards to their critiques of productions.  Too often, journalists become the sycophants and pawns in support of the houses they are supposed to critique and totally fail in their duties to question the artistic values of a production.

Casting agents in opera houses may be convenient but they are in a sense superfluous.  The speed of life on our planet has increased to untenable levels and thus with regards to opera, conductors who should be making decisions for their production are too busy to make them and defer to casting directors and agents.  Casting directors who are sometimes not appropriately competent to make casting judgments do, often relying on the judgments of friends who are agents to tell them which voice types are appropriate for a given role.  The agents themselves sometimes do not know! Worse than that, the agents will attempt to get their singers in who may be charmingly inappropriate for the role in question.  In other words, the conflict of interest between casting directors and favorite agents borders on blatant nepotism.  What if one or both of such people have racist, misogynistic or homophobic bents?  Their choices become unchecked and biased.

A propitiously timed article came out in defense of recent Wimbledon champion, Serena Williams and her sister Venus, commenting on the degree of disrespect and racial abuse these exceptional athletes have been subjected to in a sport that up until their dominating entry had been more or less a White sport.  Sports like Tennis and Golf, requiring early financial investment was economically prohibitive for many Blacks until recently.  Many consider the dominance of the Williams sisters to be offensive plainly because they are Black.  In essence, without always using the racial epithet (although it comes up), high achievers in areas considered formerly white property are treated as "uppity niggers" encroaching on areas they do not belong. The treatment of President Obama by the Republican Congress--and by their example inspiring detractors around the country-- has been abhorrent behavior tantamount to conduct unbecoming a member of the U.S. Congress.  It is as if the extreme hatred of blacks that had been swept under the rug, during the Civil Rights movements--on the heels of the murders of King, X and the Kennedy Brothers--has reared its ugly head and is becoming accepted again.  Police brutality targeting Blacks, White Supremacists targeting Black Churches as they did a half century ago, are all becoming more common place in our times begging the question if we will ever go beyond this uncivilized adolescent stage as a nation--Unfortunately a nation that casts such a grand aura that its examples become a convenient blueprint for the modern development of a new Western European culture, where minorities of different origins (whether the North Africans in France or the Turks in Germany) become the targets of racially motivated violence and institutionalized racism.

The difference between the Williams Sisters, President Obama and Opera singers is the following: There are rules in presidential politics that gives a uniquely talented candidate like Obama the opportunity to show his talent and win two American elections despite the obvious racist elements.  Despite racial abuse, the game of tennis cannot keep down players like the Williams Sisters.  They have an opportunity to compete on the even playing field of the tennis court.  There are no standards left in Opera that would guarantee fair competition in the way that the generation of Leontyne Price and George Shirley were afforded.  In essence, there is no way of monitoring racist activities in an operatic environment.

Opera itself has been not only redefined but in large part bastardized to imitate popular genres such as musical theater and film.  Criteria that are abhorrent to the art form are imposed by a great part of the leadership that does not believe the art form to be viable in our times.  The vocal talent that made so many great Black singers come to the fore has become a relatively minor part of a greater package that is part opera, part pop-culture.  Our conservatories no longer prepare students thoroughly enough to meet the challenges of the field.  Thus raw Black vocal talent often go unrefined, giving fodder to the racist canon that Black singers are, beyond native vocal talent, otherwise unprepared.  American Opera houses are importing singers from Eastern Europe and Asia for their Young Artist Programs!  In some cases these singers of the East have better vocal preparation, but they too lack certain elements of the operatic package.  Why then are they chosen over viable Black and Asian Americans?  One must wonder?  Can Asians pass for White more convincingly than Blacks?  Are Blacks of less pigmented skin more likely to get hired than very dark Blacks? The questions are endless!

How viable is a career for Blacks in Europe these days?  By and large there is more opportunity in Europe and Blacks (particularly Black Americans) are liked and are still considered exotic in a sense. However, competition in Europe is fiercer than ever. After the fall of the Berlin Wall, the East, full of grand vocal talent looked West for opportunity.  The former Soviet Block, the Chinese, Mongolians and Armenians are joining the Koreans in dominating vocal competitions.  The Scandinavians, especially the Swedes, have a grand tradition and are in the mix in much greater numbers than before.  Germany, Austria and Switzerland have become the battle ground for operatic competition and there are not enough jobs to satisfy the saturated field of aspiring singers.  Eastern Europeans and Asians are preferred to Blacks now.  

One of the artists' managers that I often recommended to my singers responded disturbingly to me once that a particular African-American singer was too American for their taste and they did not feel this singer would succeed in the European market (although the singer has already been successful in Europe).  I never got that response when I sent Caucasian Americans to this agent.  How else is an American supposed to be?  Does the singer not transform onstage with his/her character?

Not every negative comment made to a Black singer is racist.  One excellent conductor told me after I auditioned with Siegmund and Otello that he felt my voice lacked a certain concentration for the dramatic leads that I would do better in such roles as Mime and Herod and that he would be happy to recommend me for such roles.  He also said it would be difficult to be cast as an Aryan demigod in a country where Aryan-looking singers are plentiful.   This was logical! At the time of the audition he was correct.  I was in the middle of my transition to tenor and although I displayed an even voice, I was the first to say to myself, this is not yet ready for prime time.  Yet, given the poor representation of Blacks on the operatic stages of the world, it is not offensive to question whether race-based bias is at the core of it.

That no one, not the great Black singers of the past, nor the current generation of working Black singers, feel safe enough to address the question, for fear of retribution, is precisely why this issue needs to be addressed.  Should Black singers be afraid to discuss this for fear of being sidelined represents a level of oppression that suggests privileged people have something to lose in addressing such an important question, which has been addressed in virtually all other art-forms and disciplines.  Opera lags sadly behind in that regard.

Parenthetically, in my early days in the United States, I had two close friends: one was Portuguese and the other Dominican.  My Dominican friend was darker in skin color than me and in every sense looked like a Black young man.  Somehow we got into the conversation of what made Haitians who share the island of Hispañola with the Dominican Republic different.  My young friend calmly stated: "You are Black, I am Hispanic."  So does the United States Government define it.  The choices on an official U.S. document with regards to race is suspect: A) Caucasian B) Black (not of Hispanic origin) C) Hispanic D) Asian, etc...  Thus one who is Black but born in a former Spanish colony is considered Hispanic.  The formerly enslaved Black American is seen as the lowest among the races, and thus the Hispanic makes a political choice to distinguish himself from Blacks who may be closer in heritage to him than his former Spanish colonizer.  Consequently Hispanics fare a great deal better in the Operatic world, whether Black Hispanics or Caucasian-looking Hispanics.

This racism is deeply woven in the fabric of American History and World History. As much as individuals may make a choice to put that past behind them, the nature of historically privileged  institutions, the Opera house being among the last bastions of such distinction, is to preserve such an image, whether intentionally or unintentionally.  Privilege in a Eurocentric society is equivalent to Caucasian.  To expect racism to disappear from the face of the world is naive at best, unless we are visited by a culture from beyond our world that wishes us harm.  Only then will humanity unite.  To unshackle ourselves, all of us, from the bonds of racism, we need to take a journey within as a World society and analyze our historical biases and how they rule us or we rule them.  

The arts are here to ennoble us. An art form should limit racism and  not be used to limit someone because of their race.  An art form may deal with race as an issue but not be used as a tool for racism.

I am about to begin a new chapter of my life in Sweden, a country that compared to everywhere else I have lived is relatively homogeneously Caucasian.  Yet, in the time I have spent there, it is the first place where I have felt that my race is not a criterion that determines my worth as a human being or as a professional in Opera.  No, Sweden is not totally devoid of race bias.  Racism exists there too!  But the people of Sweden abhor racism and nothing is worse there than to be considered a racist.   

In light of my new situation, I could easily have resisted to write on this issue.  Yet, I teach Black singers from many corners of the planet.  I sometimes advise Black singers who are not my students on matters of career development.  What do I tell them about the nature of the current Operatic business environment?  I cannot tell them there is no racism. That would be a blatant lie.  Yet I cannot tell them precisely in what form racism is expressed in the business.  It can be creatively subtle or expertly masked.  Thus the only thing I can do is to begin the conversation in earnest.  This is the first of many articles on this blog to address the question of Race in Opera full-frontal.  No this blog will not turn into a blog about Race, however discussing this issue is totally in keeping with my mission.  On the top of the blog's front page is written the following:

This blog is dedicated to making sense of what we know about vocal technique, the psychology and spirituality of singing and issues that directly impact vocal pedagogy, performance and the effect of the art form on the broader social discourse...
I hope with all my heart that this topic will become something that does not scare people but inspire us all to take a good look at what our art form means to us beyond our own opportunities and safety.  We have to be willing to lose something to gain something better!

© 07/13/2015




Wednesday, July 8, 2015

Kashu-do (歌手道): STRUCTURE OF THE VOCAL FOLDS: A three-dimensional view





Fig. 1. This two dimensional view shows the “depth” of the vocal folds on the Y-axis (vertical) and the the “width” on the X-axis (horizontal)  we are not seeing the “length” of the folds, which would be parallel to the ground.  

I chose to begin with this view so that we are aware of “what we are after” as singers.  The curlycue blue arrow shows the airway (the path of the breath stream).

Our first issue is the interaction of the breath stream with the vocal folds.  The epithelium and the superficial lamina propria (Reinke’s Space) together are referred to as the “Fold Cover”, the other layers getting progressively harder (stiffer: less flexible) are called the “Body”.  We would like for the vibration of the vocal folds during singing to be isolated on the fold cover (yellow and blue).  Isolating the fold cover gives the voice a sensation of flexibility: the type of sensation we identify as heady, fluid and tension-free!  I call this the Flag and Flagpole Effect.  For a flag to flutter freely in the wind, it needs the structure of the firm flagpole to steady it.

BUT HOW DO WE ISOLATE THE FOLD COVER?



Fig. 2A.  This animated gif simulates the Flag-flagpole Effect.  The body of the fold the muscular red portion and the medial yellow portion are still, while the outside layer, the cover, oscillates with the movement of the breath (not seen).





Fig. 2B. This second animation shows a flexible body that allows the entire mass of the folds to participate in the vibration.  If the entire mass of the folds is active in the vibration, the sensation is one of tension and inflexibility.  Greater breath pressure is needed to maintain the vibration.  It is far greater work and it tires the voice.  The question remains how do we get the body of the folds to be firm enough such that the breath stream activates the cover only?

Dr. Zhang, Zhaoyang at UCLA, in a 2008 article shows that a stiffer fold body will isolate the vibration of the vocal folds along the mucosal edge. These two images from his article illustrate the different modes of vibration:

Fig. 3A. This first picture represents a model of loose fold body and cover.  When there is not enough antagonism between the Thyro-arytenoid group and crico-thyroid, the body (represented by the leftmost blue structure) vibrate with the cover (rightmost blue structure. The red structures represent the same two structures at rest in order to show relative movement).  The vibration will tend to be more difficult in such a case. More sub-glottal pressure will be necessary to start and maintain the vibration.  (This animated gif and the following one represent the left fold).


Fig. 3B. This simulation, on the other hand, represents a stiff fold body (leftmost blue structure is still) rendered by contractions of both main muscle groups.  This antagonism makes the fold body less mobile and isolates the vibration of the folds along the mucosal edge (cover, represented by mobile rightmost blue structure).  The antagonism between Thyro-arytenoid and crico-thyroid also increase the contact area along the mucosal edge.


LET US LOOK AT THE MUSCULAR STRUCTURE THAT MAKES THIS HAPPEN?



Fig. 4. This is a similar two-dimensional view of the folds but more anatomically complete.  On the right side of the picture, I draw a red line from the top of the epiglottis around the vestibular fold (false vocal fold) around the true fold and down to the trachea.  This layer of tissue is one fold that covers the entire structure.  That is why we refer to the vocal cords as folds.  That tissue when it comes to the true vocal folds form the outer layer (epithelium).  That layer covers the rest of the components of the entire vocal fold structure.

NOW WE TAKE A SUPERIOR VIEW OF THE FOLDS.  THE TRADITIONAL VIEW FROM THE CAMERA OF A FLEX-SCOPE



NOW WE WILL LOOK INSIDE THIS STRUCTURE



Fig 4B. Let us concentrate our attention on the two lateral muscles on each side, the Thyroarytenoid (also called External or Thyromucularis) and the Vocalis muscle (sometimes called Internal or Thyrovocalis)! When these two muscles contract, they contract in opposite directions.  When it contracts, the Vocalis thickens the vocal folds vertically (gives it more depth—See the first pictures to have a perspective—greater contact area: more on contact area later).  The Muscularis contract the folds in the opposite direction also helping create greater vertical mass. (The Muscularis also contracts, slightly inward, which appears to have a secondary closure function).  When the two muscles are active together in opposition to the Cricothyroid (see below), they create a dynamic that renders them stiffer and less flexible.  When the muscles are stiff (and by proximity, the medial layers as well), the outer layers (the cover) alone respond to the movement of the breath stream.  This allows the tone to feel more fluid, less resistant to the airstream. What we identify as the head voice sensation.  The action of the Muscularis is at least equivocal. Although its action shortens/thickens the vocal folds, the fact that the CT is pulling on the Thyroid cartilage on the same vector as the Muscularis makes the exact nature of its contraction difficult to gauge.  Even though the Muscularis is a thickening partner to Vocalis, most articles and books give the task of vocal fold thickening to the Vocalis.  More interesting is the slightly inward angle of the contraction which contributes as a secondary adductor.

LET US ADD ONE ADDITIONAL ELEMENT: FUNDAMENTAL FREQUENCY (PITCH)

Given an appropriate dynamic between the two intrinsic muscles of the the vocal folds, pitch is pretty much controlled by the contraction or relaxation of the Cricothyroid Muscles.  They are included in the above picture but not labeled.


Fig. 4C. This picture, very similar to the one above it, has pointers to the cricothyroid muscle.  Let us have an outside view:


Fig. 4D. Looking from the outside we can see that when the cricothyroid contracts (contracts toward its point of origin the cricoid cartilage) it would pull the thyroid cartilage downward.  Looking at the picture directly above (inside view), it is clear that the vocal folds are attached to the Thyroid cartilage on the inside.  When the thyroid cartilage is tilted downward, the vocal folds stretch and are set up for faster oscillation (vibration) and therefore higher frequency (pitch).  We will discuss the mechanics of vocal fold oscillation later and how “shallower” folds (less deep) make for faster oscillations and higher pitch.  For now let us consider the dynamic antagonism between the three muscle pairs (one set for each fold): Thyro-muscularis, Thyro-vocalis and Crico-thyroid.

 The Thyro-arytenoid (TA) pairs (vocalis and muscularis) must relax to allow the stretching/thinning of the vocal folds that makes for faster oscillations and higher frequencies.  However, the lengthening of the folds help maintain the stiffness of the fold body as long as the TA group continues to be active and does not give in completely to the contraction of the Crico-thyroid (CT).  Ideally, the thickness (depth) of the folds change with pitch, but the stiffness of the body is maintained as long as there is enough antagonism (opposing action) between the three muscle groups.

The question in the singers mind will always be:

HOW DO WE ACTIVATE THESE MUSCLE GROUPS?

The singer’s experience is basically sensory.  Indeed we can only activate these muscles by having experienced certain sensations associated with their function.  Two basic sensations are Stretch and Substance.  When I sing a relaxed high note softly (a sensation akin to falsetto or flute-voice), we have a feeling that we can keep going up without problem, as if we can continually stretch. In fact there is a sensation of lengthening.  A sensation of substance, meatiness, full-bodyness is experienced when I sing a relaxed low note.  In both situations, the experience is one-sided.  If I increase pressure, the stretch-dominant note tends to go toward falsetto (over-stretch that cannot endure the increased breath pressure, causing the back of the folds to open--more on fold closure later).  Increasing volume on the  substance dominant note is easier, because the vertical fold mass is enough to endure the increased pressure. However, it becomes progressively difficult to rise in frequency because the set-up is one-sided in favor of the Vocalis muscle that governs thickness.  

In order to effectuate a gradual crescendo without loss of balanced coordination, both sensations must be engaged before increasing the tone thus (I chose to begin on Db4, right on the muscular balancing point of the tenor voice):

video

The next two videos show a soprano dealing with balance on both sides of the issue:  the tendency to lose stretch on the way down and to lose substance on the way up.  (Of special note is that the soprano has an excellent F2 dominance in her middle range--This will come up when we discuss resonance).

video

video



The state of the tone before the crescendo (we will soon bring breath pressure and fold closure into consideration) is interesting.  It is falsetto or a soft head-tone?  By our definition above, head-voice, is essentially proper muscular coordination including, appropriate balance between substance and stretch.  If the TA group is appropriately balanced throughout the changes in CT contraction and relaxation (pitch), the vibration will be isolated on the cover and the tone will feel heady and released.  However, we take for granted that fold closure and breath pressure play appropriate roles.


LET US LOOK AT THE ORIGINAL PICTURE WITH CLOSURE AND BREATH IN MIND!


What happens if the two folds close too hard against each other? The fold cover would be pressed against the body (muscular layer) and would not be free to oscillate.  In such a case the vibration would have to include the entire fold structure (including the body).  The amount of breath pressure would have to be very high to maintain the vibration of greater horizontal mass, including a relatively still body.  This is why pressed phonation does not work and why it is not a remedy for breathy phonation.  Breathy phonation often occurs when the vertical mass (induced by the contraction of the Vocalis) is inadequate or the muscles responsible for bringing the folds to midline are not working adequately.

This is were I theorize (only because this has not been observed with scientific protocol yet):  I believe that when the vertical phase is too shallow, it takes the shape of a higher frequency (pitch) then is desired.  Therefore, the tendency is to sing sharp (higher frequency).  To compensate, the folds press together to slow down the opening phase of the vibration.  In this way the intended frequency is achieved, however the tone is pressed and the vibration includes the body. A singer who does not like the tension that comes with this pressed mode of singing might reduce the breath pressure by allowing the arytenoidal juncture (the back of the folds) to open creating a gap that allow the air to pass through.  There are many who use this pressed mode of phonation with leakage through the arytenoidal gap, without knowing they are doing it.  It can be done subtly or not so subtly.  When it is a minor compensation it does not sound badly and it can be difficult to convince a successful singer to change.  I have observed this strategy in many high voices, particularly coloraturas and Rossini tenors.  This approach is also common among singers of early music.

While we are on the subject of fold depth and closure, it is worthwhile here to mention that a recent paper (Journal of Voice July 2014) by Harry Hollien (University of Florida): Vocal Fold Dynamics for Frequency Change, confirmed that fold mass is basically the same for a given fundamental frequency (pitch) regardless of who the singer is.  This means that fold thickness for a coloratura or a bass is basically the same when they are singing the same pitch.  What is different is the relative longitudinal tension (tautnessof the vocal folds on the given pitch.  A coloratura singing C4 (middle C or C1 in the European system) is in her lower range and thus has relatively relaxed folds whereas a bass singing the same note is in his upper range and has much more longitudinal tension:

What was not expected was the relatively high correlation between vocal fold thickness and absolute fundamental frequency of phonation...As can be seen, the thickness of the folds appears to be reasonably similar at each fundamental frequency no matter if the subject was male or female or had a high-pitched or low-pitched voice.  Thus, it appears that the per-unit mass of the folds relates to the frequency produced no matter how massive (or not) these structures are naturally. (Hollien p. 400)
Hollien later explains the correlation between thickness of the folds, variations in length and overall mass.  Although the bass folds must lengthen considerably to achieve C4, in the end, the vibrating mass is the same as with the coloratura who does not have to lengthen very much to sing the same pitch.  This very complex experiment at least tells us there is an optimal fold depth and length index for a given pitch produced by a given voice.  If that depth/length relationship (Stretch and Substance) is not achieved, there must be compensatory measures (usually pressing and raised breath pressure).

At this juncture, we can pedagogically conclude that during phonation of a given pitch, there must be a balance between fold thickness (depth) and lengthening that adheres to a gentle closure of the folds such that the fold cover is not trapped.   The next area of concern is therefore how the muscles that govern fold closure (Lateral Crico-Arytenoids and Inter-arytenoids) respond to increased breath pressure.


Fig. 5A. The right Posterior Cricoarytenoid (PCA) muscle is removed in this picture to feature a clear view of the Lateral Cricoarytenoid (LCA).


Fig. 5B.  The rendering above takes all obstructive tissue away so we can see how the LCA attach to the muscular process of the arytenoid.  The black dot represents a swivel point.  When the muscle contract in the direction of the Cricoid (unseen here--muscle contract in the direction of the point of origin.  They are names by point of origin and then point of insertion. The CA is so named because it originates at the Cricoid and inserts into the Arytenoid. Thus Crico-Arytenoid), the arytenoid swivels bringing the vocal processes (where the vocal folds insert) inward and closing the glottis.  It should be noticed that the swiveling of the arytenoids inward also creates a gap in the back.  The arytenoids also have the ability to rock inward where the gap is.  This is controlled by the Inter-Arytenoids (IA)


Fig. 6A. The picture above shows both sets of Interarytenoids (IA): transverse and oblique.  The transverse go across parallel between the arytenoids.  When they contract they bring the arytenoids closer together and close the gap.  The obliques do the same but draw the arytenoids in diagonally. Both actions are necessary to completely close the posterior gap.

Fig. 6B. This picture gives a clearer view of the arytenoids and shows more clearly the layers of muscles.

Are these muscles strong enough to maintain gentle closure even when breath pressure increases for volume.  In other words loudness has the potential of disrupting balance if one of the muscles can not maintain its proper function when pressure is applied.  There must be a means of strengthening these muscles in balance (we shall discuss the logic behind occlusives later).

Just to be thorough, I must mention the Posterior Crico-arytenoid (PCA).  It is responsible for abducting (draw apart) the folds.  Muscular activity has been observed in the PCA during phonation, which would be unexpected.  I have a couple of theories on that.  Since all muscles are paired, it is possible that when the adductors (Lateral CA) are dominant (as expected during phonation) that the abductors (Posterior CA) provide counterbalance. It is also possible by the vector of their contraction that PCA counters the vector of the Crico-thyroid, that stretch the folds for pitch.

Finally I must address the secondary adductive function of the Thyromuscularis (external TA).  I mentioned above that this muscle contracts slightly inward and since its vector is more or less the same as the CT, when the folds are elongated, they tend to come together a little more.  This secondary adduction must be taken into account.  Sometimes inefficiency occurs not because the IAs or the LCAs are functioning inadequately but rather because the folds are not lengthened enough for the desired pitch.  There can be many variations on how a given fundamental frequency is obtained. It is theoretically possible that the vibratory cycle occur without the top of the folds closing.  This mode of vibration  would be possible for folds that are too deep (TA-hyperfunction).  This is the second sound I demonstrated on the first clip.

I will stop here for now.  We will continue soon with breath, resonance, etc...

WE DON'T KNOW EVERYTHING...BUT THERE IS QUITE A BIT OF INFORMATION AVAILABLE!

© 07/08/2015