Up & Back is a feeling or a sensation that one experiences as one sings up the scale; assuming all is working well.
Let us say that the middle full voice has appeared due to proper development and balanced working of the closer and stretcher muscles. Thus, we have a good first floor built. Then, as we step up into the second floor, we will feel the steps getting taller, smaller, lighter, thinner, and with an excited energy level. This is the “up” as we ascend the scale into the upper full voice. Yet, there is not only an “up” but also a “back.”
As the cords are adjusted for the upper pitches, there is less length, width, and depth vibrating. The air – carbon dioxide, actually – that moves through this ever smaller opening of the cords, moves at a quicker rate of speed due to the same amount of air molecules being crowded together through the small opening. This “vibrating column of air” grows taller, or goes up, as well as being directed back to the area of the soft palate and the sinuses above.
As one ascends, only the front of the cords vibrate for upper notes. The back of the cords are closed and vibration has been stopped by the arytenoid muscle system. Thus, note that the initial vocal tone is still being produced within the laryngeal area at the level of the vocal cords. Due to the adjustment of the cords, the “vibrating column of air” is directed up and back which gives the singer the feel that the upper notes are somewhere in the head; around and above the area of the ears!
The movement of the air, the air filling up the sinus cavities, and the bones of the skull and face vibrating in sympathy with this moving air is all felt by the singer as the voice is functions well. This physical reality that causes a certain sensation is what we might call the second floor. We get there by stepping on the staircase “up and back.”
The cords are adjusted properly for the pitch being sung. The vowels are adjusted to be the right size and shape for that pitch. These adjustments at the level of the cords cause the moving air from the lungs to form a column of air molecules that are vibrating to be directed in a direction – up and back.
A singer has this good feel. This feel is not the source, but a reflected image of what is happening nicely at the source. Up & Back is the sensation that we have when singing the upper full voice; high notes done right!