Just listen, all the gestures are in the music.  
(Tulio Serafin to Maria Callas)

More fundamental than thought, the ear is the «first brain» of the singer, the living source of the voice.

Its primary function in vocal production is a most precious guide in the acquiring and mastering of a vocal technique.
In preceding the musical line, the ear becomes the leading figure in all aspects of breath control and the shaping of a phrase.
It becomes the essential element of our physical and musical perception
Profoundly active inside the body, the ear registers every movement and situates the centre of gravity through which we anchor the voice. It establishes the vertical alignment that allows the voice to project, to fly "on wings of song", so to speak.

In evoking the imagination by the awakening of the ear, we allow our audience to hear the unsaid, to enter into the infinite space of the work,
there where the laws of the stage are such that it is the unsaid, the inexplicable, that seizes the heart, that electrifies the public.

Concretely ...