Let It Happen – Part 3: There’s a tongue in my cheek!
In the previous two articles, I have addressed the idea that we can start a flow of energy which corresponds with breathing, and then we can let it happen. There are, in my opinion, various imagery ideas that can be used to keep our minds in the “allowing” mode rather than the “controlling” mode. Since it is inevitable that we will think about our throats and mouths at some time during singing, then what can we do here? Again, I think that the language and imagery we use is extremely important. I was reminded of this whilst attending a recent event organised by the British Voice Association. Several mentions were made of sub-glottic pressure, and the need for increased sub-glottic pressure when raising pitch. To my mind, the word pressure immediately causes more pressure and tension than is necessary. If I were to say to a student that they need to increase sub-glottic pressure, then I can be fairly sure that they would quickly increase tension in the upper chest, across the collar and in the neck. So, why the need for sub-glottic pressure?
Fluids (gases and liquids) flow from areas of high pressure to areas of low pressure. When we see weather forecasts on TV and we have an area of low pressure over us, we know that air will rush in from an area of higher pressure, causing wind. If that area of higher pressure is somewhere cold, then it will bring cold winds – and associated weather! When we sing, we need air from our lungs to pass through the larynx. Therefore we need sub-glottic pressure (pressure in the area below the larynx) to be higher than supra-glottic pressure (pressure in the area above the larynx). More often than not, supra-glottic pressure is ignored, because whether consciously or sub-consciously, people assume this to just be atmospheric pressure, and therefore something that we cannot affect. This isn’t entirely accurate. After passing through the larynx, the air must negotiate other parts of the vocal tract and then the mouth before it emerges into the atmosphere. The first part of this is the pharynx.
In this diagram, the label of the pharynx is pointing at an area called the oropharynx. For simplicity, we can assume this to be a tube (cylinder) shape. The diameter of this tube can clearly be affected by pulling the tongue back and making the space smaller. Any fluid flowing through a tube will create resistance to its own flow. According to Poiseuille’s Law, this resistance can be expressed as follows.
where η is the viscosity of air (constant in this case), L is the length (again we will assume it is constant) and r is the radius (cross section of the tube). If we were to half the width of the pharynx (radius) by pulling back on the tongue, the resistance to the air flowing through would increase 16 times. In other words, in order to get the same flow of air through the larynx we would need to push air sixteen times harder, or increase sub-glottic pressure sixteenfold. Conversely, if we allow the tongue to relax forwards in the mouth, we take away resistance. We retain the pressure differential that is required for airflow not by increasing sub-glottic pressure, but by taking away things that are in the way. Suddenly we find that things can flow, that unrestricted movement can occur, and that we can go with the flow. Undoubtedly there is a release of both tension and conscious control when this happens. Sometimes a feeling of resistance makes us feel secure, and makes us feel that we can “go at it” a little more confidently – just ask any golfer whether they prefer putting uphill or downhill! However, in accepting and going with the flow we can find an easier relationship with our own voice and our own expression.
So, my tongue isn’t really in my cheek. Hopefully it is remaining in my mouth rather than in my throat. Gormless expressions really can be of benefit in singing. Slack jaw, lolling tongue, open throat and flowing sound. After all, why would we want to make singing more effort?