Comment: This lessons explains the real meaning of "appoggiare la voce" or the ability to "lean" on the voice. It has nothing to do with breath support as is the popular point of view. There is also a discussion of an "open" vs. a "covered" sound.
Quote: Appoggiare la Voce: Italian, "to lean on the voice." Taken at face value, this early pedagogic directive appears to be nonsense, since vocal tone, like that produced by all other instruments, is merely a series of complex sound waves that cannot be "leaned" upon. The structure of the vocal mechanism, however, suggests a possible explanation for the coinage of such a phrase. The larynx, a respiratory organ which is also a part of the digestive tract, can be moved up and down to permit swallowing and ingestion. When used as a vocal organ, this mobility permits it to function efficiently as a primary resonator. Four paired suspensory muscles participate in stabilizing these movements, and when held in balanced tension, they coordinate to provide the resistance necessary to energy economy. When the suspensory muscles are maintained in equilibrium, the singer is able to "lean on the voice" and sing without fatigue. (A Dictionary of Vocal Terminology)