One paper I read a few years ago (I will post the article’s information when I find it again) stated the obvious: Regardless, of fundamental frequency, the net weight of the voice is constant. The voice doesn’t become suddenly “lighter” when we go up in pitch nor heavier when we go lower. For some of you, this may sound radical, because that is all you ever heard. Let us be more exact! The vocal folds change shape with changing pitch/vowel combinations. The folds are 3-dimensional. They can change in length (horizontal), in depth (vertical) and width (medial/closure aspect) if we are looking at the singer’s frontally (the way the singer traditionally faces the audience).
What we call weight is the way we experience medial tension (or how tightly the folds close). Yet a part of the paradigm is that the folds must close firmly. I’ve been hearing this for a long time and honestly, following that advice only contributed to my less than superlative former baritone incarnation (I was always a tenor but trained as a baritone). Here’s the kicker! My favorite singer in those days was the great Domingo, whose phonation mode became increasingly about “fold closure.” In my experience, fold closure is the easiest way to get glottal resistance as to avoid leakage–especially when there is no knowledge or consideration that the y-axis (vertical contact area) contributes greatly to glottal resistance. Appropriate resistance produces the high overtones we need for vowel clarity and for the singer’s formant. In a spectrogram, the singer’s formant (the ring of the voice) manifests as a cluster of harmonics combining the influences of formant-resonances 3, 4 and 5.
A strong glottal resistance is needed to produce strong harmonics. However, a medial squeeze is not the only way to get a strong resistance.
In Journal of Voice, Vol. 32, No. 1, 2018, Li, Scherer et al. concluded that the vertical contact area, controlled by the activity of the vocalis muscle produce a deeper, bulgier fold cover that approximates the folds more closely. There are even experiments and theories that suggests that the folds might only need to come close enough to each other to create the desired acoustic results. That can only happen with “relatively deeper folds.”
I say relatively because the folds do not have a constant depth for all pitches. The folds become less deep as pitch rises but the question is how deep/shallow relative to the pitch in question? The right depth and length combination produces conditions for a softer closure and above all:
An isolation of the fold cover. When the folds are lengthened and appropriately deep, the muscular layer of the folds become stiff enough to isolate the fold cover to vibrate freely–Zhang et al.
Therefore, we must avoid the false narrative that more closure and less fold depth is the path to a strong glottal resistance. It’s one path! That path is closer to a pop singing strategy than an operatic one. A medial squeeze is easier and gives immediate results of a type. But those short term results are also the ones that produce limitations later. An appropriately deep, long and gently closed folds is the path to flexibility (morbidezza). The larynx is then able to relax down to a low position without being pressed down. That part is simple.
A tone that is relatively pressed, even a little contributes to a higher larynx, which makes the transition to the second resonance area (F2) rather difficult. In that case, one must make a concerted effort to push the larynx down to lower the 1st Formant resonance to facilitate the process of the second to take over.
Guess what? A lot of singers have successful careers doing exactly that. So I’m not saying it’s not possible to have a little squeeze and be successful–especially singers with relatively thin fold covers by nature. The lighter voices!
As a dramatic tenor I don’t have the option of pressing. I must do it the best way possible. Teaching the folds to stretch and not lose too much depth is not easy. Some singers grow up with relatively good habits and can prosper with very little intervention. Rarely the case with dramatic voices–especially dramatic tenors! Our ultimate success as dramatic singers in the world of opera depends greatly on the good fortune of meeting a teacher who matches our needs. And since I personally do not like to rely on luck, and I was not fortuned with wonderful vocal balance in my youth, I figure being as much informed about the voice is the best way to even the odds.