To know the result before we act is the "golden rule" of singing.
When your tone emerges from silence into sound without effort, focussed, yet free, with sufficient energy to release, or restrain, back of it, you are one of the greatest singers.
To sing well you must be continually feel "hollow-headed," "full-throated," "broad chested" and "tight-waisted."
Do not "hold" your tone, spin it. Hold your breath.
No matter what the character of the voice be (bass tenor, contralto, soprano) it should feel high placed and sound high focused.
Vocal Wisdom: Maxims of Giovanni Battista Lamperti by William Earl Brown (1931)
Such an interesting book Vocal Wisdom, which appeared a year before Marchesi's The Singer's Catechism and Creed in 1932. I pick it up often, and always have the queer feeling that I am reading it for the first time, even though I have a lot of it committed to memory. It comes from left field, right out of the zone, full of zen-like statements that make me stop and think. Feel too. And that is the point.
I see Vocal Wisdom as being full of vestibular cues which give the reader a very clear understanding of the "singer's sensation," a term I find myself using when referring to "breath," which, for Lamperti, was something more than air in the lungs.
Spin the tone by holding the breath? Hollow-headed, full-throated, broad-chested, and tight-waisted?
These cues can confound the student of anatomy and physiology, especially if said student believes singing to have a purely mechanical basis. All parts, no whole, I am amused by the student, who, when asked about breathing, proceeds to give a lecture about the muscles of the torso.
"It's great that you know how they work!" I say. "But how do you feel when you breath?"
If they fumble for words, I know they 1) aren't in touch with their feelings, 2) aren't used to describing them, 3) lack skill, or 4) the ear is underdeveloped. Whatever the reason, progress begins when their feeling sense becomes as clear as their vowels, which amounts to the same thing.
If they describe sensations of lift, well-being, extension, elasticity and buoyancy which pervade the body, we're good to go. If not, one of us has to do a lot of heavy lifting.
Singing is a feeling. Listening is a feeling. The ear is the body after all. When the student feels "inspiration" from pelvis to top of head, they are ready to sing.