Practically applied, the more smooth and even the flow of breath is for the singer, the more smooth and even the vocal sound will be, ultimately. Just as an over-exertion or under-exertion of force causes a harsh or thin sound from a violin, so the force that the breath is allowed to apply to the vocal folds will change the vocal sound also. This why voice teachers should take time to work on breath exercises with their students, and students and performers should take time in practice to exercise their breath properly.
A few problems that can take place in the vibrator mechanism of the voice include tension in the breathing and articulating musculature (which affects the tension of the vocal muscles), excess breath pressure pushing against the vocal folds, and not allowing the vocal folds to close completely (resulting in a breathy sound). Proper approach to phonation is vital for singers, and voice teachers should understand the process well in order to identify problem areas for their students.
Since the richness of the vocal tone is affected directly by the resonators (larynx, pharynx, oral cavity, nasal cavity) the position and shape of these areas is important for singers. Having an "open throat" is key to good singing, and can be achieved mostly by avoiding tension in the jaw, tongue, throat, and abdominal muscles and by proper "placement" of the vowels sounds.
Through the practice of proper coordination of the various parts of the vocal instrument, a singer can develop his voice into a highly versatile instrument. More ideas on practical vocal technique will follow in later articles.
What are your thoughts or questions about the process of singing?