Onset is a term used to describe how we initiate a sung pitch: the first moment of our tone. How we begin a note influences the quality of our sound throughout a musical phrase. If a phrase begins with good breath support and efficient vocal fold closure, good tone is more likely to be achieved and maintained. Conversely, if we don't start our phonation well, it is difficult to make an adjustment mid-phrase.
Here are examples of how we can lead into a sung note:
We can use various onsets intentionally for different timbral effects, however, to protect our instrument and to achieve a "pleasing" tone, we want to shoot for the BALANCED ONSET most of the time.
To get used to finding and feeling the difference between different onsets, try repeating a single pitch in your comfortable range, alternating between the aspirate, glottal, and balanced onsets. Separate each new onset with a good breath. What does your throat feel like at your glottis (the vocal cords and the space between them) on each onset? Do you feel pressure build under your glottis before you sing or do you feel air pass through before the tone starts? Does your breath support change with each onset? Notice the contrast in sensation between each. Can you repeat a balanced onset consistently?
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