So far a large number of ooks on music have published at home and abroad. In the field of the vocal music have come out innumerable studies, in most of which the vovalization for exapmle should be performed almost totaly in the diaphragm or the abdomen. As mentioned in this study, this is the vocalization method in the resonance area Picture A, centered around the diaphragm. However, the resonance area, Picture B, larger in area than Picture A, shows that the resonance goes physically much larger with the vocalization in the delicate way of viblation caused by the flexible reation(knee reation) , of course under consideration of the diaphragm excercise.  Morever, in order to enlarge the movement of the Picture B, the paramera viblation helps the resonance to be produced even larger. On the contrary, subtly reaction the knee, the voice volume is controlled.

The above mentioned is thought to be the change of the source.