When focusing on relaxation flowing down your rear back, starting from the end of your natural (and non-forced) inhaling, your air column – or better, your sound column – must be felt as deep as possible, in order to reach its stable position, as though you were sitting on the radiating vibration, which then excites another column, a physical one this time, your cervical/vertebral spine.
In correct emission, the larynx is lined up against the cervical spine which, excited by the vibrations transmitted to the larynx by the vocal cords, starts to sing of its own accord.
Under these circumstances, the larynx is excited exactly as the strings of a violin. It is the strings that vibrate and the violin that sings. When the posture of the singer is well aligned, his larynx excites the vertebral column just as if it were that little piece of wood inside the violin that is called the “soul“ of the violin. Its purpose is to carry sound from the anterior plate to the posterior plate. We want to make a column of sound, resonant over and under the glottis, not a column of air, as myth would have it.
(…) But it is one thing to talk about a column of air with all the ideas that are usually associated to it : the push, the pressure, tension on the cords, etc.., but a column of sound is something altogether different.
The latter implies relaxation, a measured and tranquil expenditure, being on the lookout for tension, to reduce effort, to avoid pressure.
Alfred Tomatis, The Ear And The Voice
(translated by Roberta Prada and Pierre Sollier)