ABSTRACT
This chapter reviews care of the professional voice user. As the discussion proceeds on professional voice users, it is necessary to characterise the vocal organ. It is important that the entire body is considered. That said, the vocal tract is generally divided into power source, true vocal folds and resonators. The critical issue when discussing the power source is the development and maintenance of a column of air under pressure, which is presented to the subglottis and glottis. Whereas the diaphragm is the essential muscle for the act of inspiration, expiration – and in particular controlled expiration – is necessary for vocalization. The length of the true vocal folds varies in adult humans from approximately 15–18 mm in females and 20–22 mm in males. As Scherer points out they can only vibrate together and create sound when held relatively close together, in approximately 10–15% of their adductory and abductory range.
