PITCH 407 



Pitch, or tone-height, is a function of the frequency, i.e. rate of 

 vibrations. This may be proved by ruiniing a gramophone record 

 at various speeds. When running at its slowest the plate of the 

 sound box is receiving and transmitting vibrations at the rate of 

 about 100 per second, and one hears a bass voice. As the speed is 

 increased the voice rises in pitch till it may be a distinctly light 

 tenor with 500 vibrations per second. 



The av^erage limits for the human voice are given in Table LXII. 



TABLE LXII 



(Sabine's Notation) 



We derive the musical notion of high and low pitch from the 

 rise and fall of the larynx in the production of sounds — an entirely 

 subjective phenomenon. The pitch of the voice may be altered by 

 voluntarily lowering the position of the larynx during phonation — 

 a knack acquired by training. Hudson-Makuen has used this fact 

 in correcting the high-pitched or eunuchoid voice which occasion- 

 ally occurs in men otherwise normal. A somewhat similar process 

 occurs in the acquirement of the deep voice cultivated by many 

 women who have occasion to lecture regularly. Prolonged use of 

 the lower register gives these people a peculiar " falsetto " booming 

 voice. The pitch of a tone, from a physical point of view, is absolutely 

 defined by its vibration number. High-pitched notes have a higher 

 rate of vibration than low-pitched notes. Alterations in the pitch 

 of a note are probably brought about in the larynx by altering the 

 tension of the vocal cords, by the action of the crico-thyreoid 

 muscle — the greater the tension of the vibrating membrane, the 

 higher the pitch of the note produced. The part of the cords free 

 to vibrate may be varied by the approximation of the arytsenoid 

 cartilages to one another, A long cord vibrates more slowly than 

 a short one. This accounts for the high-pitched voices of children. 



In addition to this, it is common knowledge that when the force 

 of the blast of air is increased, the pitch of the voice rises. There 

 is thus a tendency to sing sharp when forcing the voice, say in a 

 large badly built hall. 



In one and the same larynx, different parts or regions of the 

 scale are produced in different ways. Those notes of the scale 

 which are produced by the same means are said to be produced 

 in the same register. Thus, we produce deep notes in the chest-. 



