The Physiology of Belting – International Voice Teachers of Mix

The Physiology of Belting

Weekly Teaching Tip – September 17, 2012

Teacher: As I taught in various Camps and programs this past summer, I have been reflecting a lot on all the great information and presentations at the IVTOM conference this July. I was so pleased to see so much good scientific information explaining and documenting what we know from experience about the effectiveness of Mix technique. I am left, however, with some questions about a few pieces of missing information.

First of all, it was great to see the presentations of graphing the differences between belting, mix, and head voice in terms of formants and harmonics that are emphasized differently in each… I was troubled however that we don’t have any empirical proof of what makes one singer more able to belt higher than another, from a muscular point of view…

Dr. Noe: This is comparably easy to answer. The ingredients of a gifted voice (regarding strength) are: 1. a narrow epilarynx tube 2. strong TA and CT muscles 3. thick and strong mucosa with an optimal fiber-liquid concentration 4. symmetry between the left and right vocal folds. All in all strong vocal folds with a narrow epilarynx tube

Teacher: It was mentioned that any voice can be trained to belt.Those of us who have sung and who have worked with singers over the years, know that this is not the case.  Otherwise we might all be great belters, right:)?

Dr. Noe: There are people who can only whisper or speak very softly (you don’t see them as a voice teacher, but ENTs see them). In this case both of you are speaking of different things. Chest belt is functionally and acoustically shouting. Of course an average voice can shout a few tones or at least one tone. But artistically and musically useful belting is another thing (range, beauty, pitch.) Anyone can shout, but for us only the musically useable belting is the real thing. Some voices are more conducive to belting, but through coordination and strengthening any singer can learn to sing more powerfully. Remember there are also psychological, muscle memory and musical taste issues that make it more difficult for some people as well.

Teacher: I feel like, in order to really be able to give realistic guidance to students, we need to know what this difference in muscular capacity is.

Dr. Noe: We (I) know and you can hear it mostly after a short audition or few lessons (smaller voice and range, tiring out sooner): there are physiological limits. With the best technique not everybody can be trained to serve with 120 miles in tennis, but perhaps he can get 10% more with a good coach.

Teacher: This is one reason that I was pleased to hear something so concrete from Dr. Noe regarding the ability to increase the strength of intrinsic muscle strength (for longer closed phase) is limited to approx. 10%… and that what I call “edge” exercises or spoken attack is one concrete way to increase this strength.  So at least we have a path to increasing cord closure phase and a realistic idea of how much we can improve our natural ability….I had hoped to see the difference in use of muscles in the laryngeal karaoke part of the conference.  I thought that the teacher/singers who demonstrated did a great job of demonstrating the same note sung with mix versus belt coordination.  With the scope that was used (no strobe), it was impossible to really see a difference.

Dr. Noe: It takes experience to see it even on stroboscope. Garcia understood with a simple mirror that the closure was the point (fast and complete, unfortunately he named that exercise coup de la glotte, which upsets every half knowing teacher). I wanted to show it to you on the video with the excised lanrynges, but did not succeed because of the lack of contrast in the projector. We should have taken the time to repeat that because it is so important. You can find it on the Krakaw video. Vennard and Van den Berg say  intermediate instead of mix and  falsetto instead of head. Then we can learn to see it also life in strobo.

Teacher: Also I understand that since we cannot insert a scope below the vocal cords, we may be unable to see the difference.

Dr. Noe: (not necessary, even then it would be hidden under the mucosa, but you would see it more or less bulging at the bottom which also would be individually different) .

Teacher: My hypothesis is that, belt could be characterized as TA predominant coordination and mix be characterized as the ability to combine TA and CT coordination and eventually shift to CT predominant coordination with high percentage of closed phase, the ability to “belt” higher is related to the ability to hold onto TA predominant coordination as we ascend through the chest/spoken voice range.  I also hypothesize that voices that have the ability to belt higher than others also have good cord edge coordination, because they seem to be able to “thin out” as they ascend through the “chest extension” range.

Dr. Noe: Your hypothesis is not quite correct. In high chest you need even more CT activation to lengthen the bigger mass in vibration, which is added through the higher activity of the TA in chest. In chest this leads to an escalation of CT against TA. The big voice cracks later, tires out later, gets his edema later and gets his wobble a little later, but it will come!!!!! Belters are like every other human. Think of smokers and drinkers. In the moment of a temporary pleasure or kind of success they are not interested in what happens in ten years. And singers have the applause of the layperson. You can read this in my chapter in Dean’s book or I can send it to you. But you have to work through it at least 5 or 6 times especially the case of the tenor who finally cracks, because the CT has the longer lever. Read it over and over and do not pass over a single word like “the TA does not only add vibrant mass, but also stiffens the vocal folds”…we are accustomed as medical students to read something over and over up to a sometimes painful torture in order to understand the function of the heart, liver, adrenal glands, brains and other organs.

As far as Mix being characterized as the ability to combine TA and CT with a high percentage of closed phase – It is important to remember that the energy feedback of the good vowel/harmonic combination helps.

And one last thing, chest belters do not thin out!!!!!, but mixers do. We have to agree about definitions: belt is chest belt and mix of the modern females is belted mix.

Teacher: Also, do you feel there is any way to scientifically explore this issue?

Dr. Noe: Yes


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