The singer’s endeavors, consequently, must be directed to keeping the breath as long as possible sounding and vibrating not only forward but back in the mouth, since the resonance of the tone is spread upon and above the entire palate, extends from the front teeth to the wall of the throat. He must concern himself with preparing for the vibrations, pliantly and with mobility, a powerful, elastic, almost floating envelope, which must be filled entirely, with the help of a continuous vocal mixture, — a mixture of which the components are indistinguishable.
To attack a tone, the breath must be directed to a focal point on the palate, which lies under the critical point for each different tone; this must be done with a certain decisiveness. There must, however, be no pressure on this place; for the overtones must be able to soar above, and sound with, the tone. The palate has to furnish, besides, the top cover against which the breath strikes, also an extremely elastic floor for the breath sounding above it against the hard palate or in the nose.
This breath, by forming the overtones, makes certain the connection with the resonance of the head cavities.
In order to bring out the color of the tone the whirling currents must vivify all the vowel sounds that enter into it, and draw them into their circles with an ever-increasing, soaring tide of sound.
The duration of the tone must be assured by the gentle but uninterrupted outpouring of the breath behind it. Its strength must be gained by the breath pressure and the focal point on the palate, by the complete utilization of the palatal resonance; without, however, injuring the resonance of the head cavities. (See plate, representing the attack.)
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The head tone signifies, for all voices, from the deepest bass to the highest soprano, — excepting for the fact that it furnishes the overtones for each single tone of the whole vocal gamut, — youth. A voice without vibrancy is an old voice. The magic of youth, freshness, is given by the overtones that sound with every tone.
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