Anthony Brown

Voice Over

In physical terms, the frequency of vibration as the foremost vocal attribute corresponds to the number of air puffs per second, counted as cycles per second (cps or Hz). This frequency is determined by both stable and variable factors. The stable determinants of the individual voice range depend on the laryngeal dimensions as related to sex, age, and body type. The smaller a larynx, the higher its pitch range. Within this individually fixed range, variables that influence the pitch of a given phonation include: tension of the cord, force of glottal closure indicated by the glottal resistance, and expiratory air pressure. Growing tension of the cricothyroid muscle (as the external vocal cord tensor) increases the vocal pitch, and vice-versa. Increased glottal closure and expiratory effort add to this tensing effect under certain circumstances. For example, 100 vibrations per second produce a low chest tone of a low male voice, while 1,000 are close to the “high C” of a female soprano.