Mechanics of Voice Production
The body part that plays a significant role in signing and speaking is the larynx or the voice box. Singing, however, requires the use of other body parts apart from the voice box. Singers are able to create sound by the use of abdominal muscles, back muscles, the oral cavity, the lib cage and lungs among others (Blitzer, Brin & Ramig 2009).
Medically, the vocal cords are known as the vocal folds, which are membranes that normally snap open while one is singing, making noises, or speaking (Aronson & Bless 2009). The vocal folds consist of five layers of tissues. The deepest of them is the vocalis or thyroarytenoid muscle, followed by the deep and intermediate layers of the lamina propria that form the vocal ligaments (O'connor 2011). During voicing, the top layer lets the last layer slide over the vocal ligaments. Air flows within the layers and causes pressure to build up and a sound is made. The softness of the sound depends on the amount of air that flows on them. When the folds snap forcefully, the airflow from the lungs increases substantially creating a greater force in the airstream from the lungs, the epithelium opens wider and forces air past them (Lion's Voice Clinic 2012). This much air release results to a loud voice. The use of excess force is referred to as laryngeal hyper function. A forceful closure of the vocal folds may result to vocal fold trauma causing tearing of folds, swelling, hemorrhages, polyps, nodule masses, or cysts. An optimal balance between airflow forces and glottal resistance is crucial. The quicker the opening and the closing of the cords, the higher the subsequent pitch.
However, there are "false" vocal folds that just sit over the actual vocal cords, which work is to prevent food or drinking from getting into the trachea during the swallowing process (Dayme 2009). As a result, these folds play no role in an individual's speaking or singing.
When a person starts singing, the first thing that happens is breathing. Breathing helps the larynx muscles to pull the vocal cords towards each other (Heman-Ackah 2006). Consequently, the vocal cords stay closed until enough pressure is build up and a rush of air gets out via the cords.
Unlike instruments that produce sound by vibration, human beings produce sound using the changes in pressure resulting when little quantities of air pass through some moving vocal cords. When an individual gets out of breath, his/her vocal cords get drawn together and no sound is produced (Davis 2007). In order to make good singing, one is supposed to practice breath control since it is like the engine that makes the singing machinery to function well. Moreover, when a swelling resulting from poor singing, or smoking interrupts this gradual opening and closing of the folds or small lesions, which cause hoarseness, the quality of the voice is altered and becomes bad (Haston 2007).
If a singer develops small spaces between the vocal folds that may be because of a mild vocal fold weakness, masses like nodules, cyst or polyps, vocal fold scars or swelling, there could be escape of air in the phonatory cycle and the vocal folds epithelium may not be in a position to close completely (Seikel, King & Drumright 2010). Furthermore, an incomplete vocal fold closure forces a need of more energy to produce higher airflows from the lungs to increase volume and maintain phonation. This need of more energy results to a greater susceptibility to fatigue. The effect is also seen in the lungs thus producing a softer sounding voice (Seleshanko 2007). Many singers with incomplete glottis closure tend to compensate by recruiting the accessory muscles of phonation making them suffer from the consequences of laryngeal hyper function and those effects associated with incomplete closure. Likewise, this tendency leads to voice fatigue and largely, a serious vocal fold injury.
Anatomy and Physiology of the Voice
Resonance and Amplification
Voice production practically involves all systems of the body. It begins with breathing where the volume of the lungs expands and air rushes out to fill the space. Therefore, the resonance chamber and voice amplifier is the vocal tract that includes the pharynx, the palate, the tongue, and the mouth, the back of the nose, the sinuses, as well as the head. When sound leaves the vocal folds, there are waves that keep bounce and rebouchnig on the vocal tract (Blitzer, Brin & Ramig 2009).
Sound gains energy in the areas amplified by the specific shape of the vocal tract when it vibrates in the vocal tract. Sound, on the other hand, loses energy in the areas that are dulled by the form of the vocal tract. Since the individual's shape of the pharynx, oral cavity, the head, and nasopharynx are different, intensification of the fundamental frequency occurs differently and in different degrees from one individual to the other (Davis 2007). The harmonic frequencies are the ones that give a "ring" to each voice allowing us to differentiate the sound of one individual to another. Harmonic frequencies with the highest energy are referred to as formant frequencies. However, one can change the shape of the vocal tract by varying the tongue's and uvula's postions, shape of the pharynx changing the characteristics of the harmonics and formants hence achieving a projection.
A more open mouth and an oral cavity achieve greater amplification of the voice. To achieve this, one is supposed to optimize the best locus of his or her tongue and its base, the palate, the jawbone and the lips. A correct neck position, that is, a neutral position of the head, and a straight spine, produces a straighter vocal tract and enhances resonance and projection (Chete 2011). The uvula's and the palate elevation help in opening the vocal tract at the back of the oral cavity sealing the nasopharynx and minimizing hyper nasality. When the tongue is relaxed at the base its tip rests in a forward position, the oral cavity lengthens, and the tongue base widens creating a longer and greater amplification diameter (Greater Baltimore Medical Centre 2010).
Airflow and Breathing
Vocal production is a complicated process that involves most body structures especially the lungs, abdomen, back and the chest (Barton & Dal Vera 2011).
Breathing is important in the functioning of the voice as it propels it and gives it strength (Kreiman & Sidtis 2011). It determines how loud the voice is. The voice cannot function without breathing.
The lungs have the capability of expanding in all three dimensions, the greatest excursion area being down. The lungs situation is in the chest cavity and is separated from the abdomen by the diaphragm (Lion's Voice Clinic 2012). They are encased by the ribs on all sides, which limit their outward expansion leaving the great expansion room on the down part that is towards the abdomen. The diaphragm moves down with inhalation and moves up on exhalation. The contraction of the diaphragm and the abdominal muscles relaxation causes the siphoning of more air into the lungs during breathing (Phillips 2003).
The chest allows the control of the voice by expanding when one breaths in to allow more air hence enabling the voice to be stronger. In this, the singer is capable of providing more power through the support of an increased breath and has control through the strengthening of the diaphragm muscle (Lion's Voice Clinic 2012).
Lung diseases such as asthma and chronic pulmonary disease resulting from smoking can limit lung function (Vendera 2007). In these cases, the lungs are capable of inhaling the same quantity of air as common, however, the force produced during inhalation decrease due to a limited recoiling inside the lungs.
Obstructive lung diseases like emphysema, obesity, and some effects of broken ribs limit the amount of air in the lungs thus limiting the amount of air the lungs can exhale. For this reason, these infections affect a person's airflow and control of it during singing. Injuries can prompt vocal fatigue and cause decreased vocal projection.
The abdomen helps to produce a suction effect on the diaphragm when breathing. The abdomen consists of the external and internal oblique, rectus abdominus as well as transverse abdominus muscles. A sustained abdominal contraction during exhalation helps to control the airflow from the lungs in the course of breathing and phonation (Vendera 2007).
Abdominal surgery weakens the cut muscles and hence the knowledge of the abdominal anatomy is critical for a voice professional considering an abdominal surgery. As a matter of fact, recuperation and strengthening of weakened muscles before resuming to a normal vocal routine is vital for the proficient voice user (Wicklund 2010).
The main function of the back is to support the abdomen and maintain balance. However, for the abdomen to support breathing, the support of the back muscles is crucial in support of its contraction efforts (Hatscheck 2012). A greater force is created when the back offers a continued support to pressures within the stomach.
Ways to Maintain Vocal Health
Plenty of Rest
A singer must know the amount of sleep he or she needs to function best. He or she should then keep a regular sleep schedule according to his or her needs (Peckham 2010). Resting the voice when possible is important and an unwinding time is essential to help one renew the lost energy that will be needed to another singing. It is important not to wait until one burns out to schedule for a downtime away from some stressful work.
For the well-functioning of one's voice, drinking plenty of water is important since the vocal cords should be well lubricated in order to vibrate with the little amount of friction (Casper, Colton & Leonard 2006). A well-hydrated body is capable of flushing out germs that cause throat infections. The water should be taken before a feeling of thirst strikes.
Singing can be physically involving, and maintenance of good health is important to successful singing. Regular exercise helps the singer to stay fit physically and mentally and increases one's energy (Smolover & Bertoli 2006). Since a singer's body is his or her instrument, any effort to improve its health eventually shows in the strength of the voice.
Smoking causes emphysema, and mouth and vocal tract cancer, which are of great negative effect to the functioning of the lungs and the throat. Similarly, chemicals from smoke cause irritation of the vocal tract membrane forcing the body to compensate this with secretions. The throat clearing further causes irritation, which is serious for one with a singing career (Peckham 2010). Smoking also causes inflammation in the throat making the singers unable to eat certain kinds of foods as they will affect their singing by causing reflux laryngitis.
Do not sing if it hurts
It is essential for singers to listen to their bodies when they feel some discomfort. When tired, it is of necessity to rest the voice and see also a qualified laryngologist in case of more than a simple cold (Klickstein 2009). A doctor should diagnose any suspected health problem.
After all, voice production is the result of the relationship between airflow, resonance, and amplification. In conclusion, knowledge about the physiology of voice production and the anatomy of the organs involved is the base to understanding the care and maintenance needed on one's voice throughout his or her career.