Your first note actually begins in the brain. The intent to sing a musical tone causes the vocal folds to begin to close. The breath then comes up from the lungs and pushes against the partially closed folds, causing them to vibrate as air escapes through them. The amount of air flowing across the cords is called subglottic pressure, meaning the air just below the glottis. The subglottic pressure is enormously important to the onset of the tone, and fortunately it is within the control of a trained singer. The production of the tone can be analyzed in three segments: the beginning, holding the tone, and ending it.
The Beginning or ONSET
The beginning of the note is called the attack, an unfortunate name given the need for gentle air pressure. Some teachers now refer to the attack as “the onset of tone.” During this phase, the breath should flow gently for a clear sound that’s free of tension. The preparation in the mind and body is crucial, and it must be your main focus since the action of the vocal folds happens on a subconscious level. To properly prepare the tone, you should think the pitch before you start to sing, not after. Too many people get nervous about the attack and just begin singing, resulting in scooping and sliding to find the right pitch. You should also prepare your body for the breath with the lifted chest and straight alignment.
Try this exercise to practice initiating the sound with air.
EXERCISE 1
- Open your mouth to a comfortable position and then inhale as if you didn’t want someone to see you yawning. The jaw should drop slightly and feel very loose. Concentrate on the sensation and the feeling of the cooler temperature of the air across the soft palate.
- After the inhalation, hold this open placement and exhale through both your nose and the mouth without lowering the yawn position. It’s particularly important to feel the air flowing through your nostrils.
- Repeat the yawn inhalation, exhale through your nose and mouth while maintaining the lifted soft palate, and, after you feel the air through your nostrils, sigh out gently on a “hum.” Make sure that this is one continuous action.
- On the next exhalation, repeat these steps but sigh on “ha.” Try to feel the same humming sensation in “ha.” This is called a yawn-sigh onset of sound, and it’s very important to master this exercise. Some singers refer to this action as “singing on the air.”
There are two common problems associated with the attack. The first is called a glottal attack, glottal stop, or hard attack. It happens when there is tension in the larynx and the cords close completely before the sound is initiated. If they are totally closed together, the buildup of too much air pressure bursts through the vocal cords all at once, creating a clicking sound before the tone. The combination of muscular tension and force between the cords will ultimately result in damage to the cords. The glottal stop is occasionally needed to clearly voice an important word beginning with a vowel, but should be approached with care. The glottal attack at its most forceful is the action of coughing or clearing your throat, something to be avoided if possible because of the friction and irritation of the vocal folds.
The other extreme is too much breathiness in the voice. An airy sound occurs when the vocal cords don’t come together closely enough during the attack and allow too much air to escape through the opening. This could be caused by too much air pressure or lack of body support. Sometimes a beginning singer will hold back and be timid about producing tone, for fear it will sound bad. Use the posture exercises to ensure that you are supporting the tone. The most sensation you should feel while singing is in your body, particularly the chest and abdominal muscles, and the vibratory sensations in your head. You shouldn’t feel anything in your throat. If you do, you’re probably either using too much force or guarding the sound too carefully.
EXERCISE 2
- Put a comb in a small plastic bag and hum across it as if it were a harmonica. Place your lips lightly around the teeth of the comb.
- Hum or sing “oo” until you hear and feel a buzz in the sound. Use this sound to hum the five-note scale.
Sustaining the Tone
Holding a musical tone once you’ve begun it is a matter of keeping a steady flow of air moving across the vocal folds to keep them vibrating. There shouldn’t be spurts of air or a waver in the tone. How long you need to sustain the note will depend on the note’s duration in the music. The best way to keep the air steady is to practice the appoggio technique explained in Chapter 3. You can control the flow of air pressure by feeling the sensation of the air in your lungs gently pressing against the inner walls of your chest and sternum. Your chest should be lifted while maintaining a feeling of expansion around the torso. Also, remember your posture and be sure to keep your spine aligned by imagining that your body is hanging from puppet strings attached to your head and chest.
Musical tone should always have the sense of continuous movement even when sustaining the same pitch. It seems paradoxical, but imagine that the air is moving steadily up from the lungs and that it doesn’t leave your body. This can help control the amount of air that actually escapes during phonation. Picture a paddle wheel inside your mouth, touching the roof of your mouth, and then visualize the air turning that wheel. The air just keeps cycling but doesn’t escape through the lips. You can add the image of inhaling the air rather than exhaling it in order to keep your throat open and relaxed. While sustaining the tone, there’s no need to move or adjust any of the articulators. Keep your tongue, lips, and jaw steady. Sometimes the hardest thing you have to do is relax and stay out of your own way.
Ending the Tone
The tone should be released distinctly and clearly. So many singers fade off at the end of the note or cut off the air in their throat. Cutting off the air will produce audible strain in the sound, and fading out the note only results in making the word unclear or unintelligible. This problem often stems from not knowing when to end the note properly. If you’re unsure of the number of beats the note should receive, it’s easy to “fake it” and hope the audience won’t notice. If you learn how to count the beats, you’ll be more secure in the release of the tone. The release shouldn’t be anticipated and elongated, but rather accomplished at the last moment of the beat. Anticipating the end might close your throat, stop the airflow, or allow you to relax the support in your body.
Once you’ve determined the exact end of the beat, be sure to use the articulators to end the tone. If you’re singing the word “love,” you would sustain the tone on the uh vowel and then cleanly and quickly place your top teeth at your bottom lip to pronounce the v at the very end of the beat.
EXERCISE 3
- Practice singing these syllables and words. Be sure to get a clear mental image of the sound and pitch before you begin the initial attack.
- Sustain the tone by imagining the moving air cycling in the mouth.
- Release the tone with clear articulation of the ending consonant or vowel at the last possible moment of the beat.
source: http://www.netplaces.com/singing/phonation/the-onset-of-sound.htm