The working of the larynx is also intimately connected with the way we breathe. If you breathe in and out normally and then vocalize on one of the out-breaths without altering your manner of breathing, you’ll notice that the resulting sound is more like a sigh than a sung tone; it will lack focus and die out very quickly— what singers call an “unsupported” tone. In contrast, a true “sung” tone has focus and clarity and can be sustained for ten seconds or more. This is because when we sing properly, the breathing and the larynx are coordinated in such a way that the breath is regulated in its flow while the vocal folds vibrate efficiently so that very little air escapes between them. When we sing and even when we speak, we aren’t simply closing the vocal folds against the normal outflow of air but coordinating the two systems to produce a focused, sustained tone. Some singers try to support the tone by tightening the abdominal muscles or expanding the ribs, which in turn increases the flow of breath through the larynx. But the vocal folds do not respond well to increased breath pressure, which creates a strained or “pressed” sound and over time can damage the vocal folds. This approach is based on the notion that, because normal exhalation is weak and “unsupported,” additional muscular effort is required to produce vocal support. In reality the voice is designed in such a way that, when it’s not interfered with, exhalation is naturally extended in a way that allows the vocal folds to vibrate efficiently with a minimum of air pressure. We are then able to vocalize in a seemingly effortless way, for extended periods of time.
In this sense, the larynx isn’t a wind instrument and is certainly not designed to be set into motion by using brute force. When we speak or sing efficiently, the entire breathing apparatus, including our neck, trunk, back, and ribs, is automatically brought into play in a way that’s finely calibrated with the closure of the vocal folds so as to create the precise amount of air flow needed to produce the intended sound. In singing, this flow must be sustained for long periods, broken up into discrete sounds, and intensified or reduced at will depending on the interpretive requirements of the music. In short, the working of the larynx requires adjustments of the subtlest sort throughout the entire musculoskeletal system, all operating in tandem to produce the full range of vocal expression.
Dimon Jr. Ed.D., Theodore. The Body in Motion: Its Evolution and Design. North Atlantic Books, 2012.