THE VOICE 281 



by Mozart to sing c in alt, three octaves above 

 middle c (2,048 vibrations), while the lowest 

 is that of Gaspard Forster, who gave a note 

 nearly three octaves below the middle c (42 

 vibrations). Musical sounds begin with about 

 32 vibrations per second. These two voices, 

 therefore, had a range of about six octaves, 

 but the usual range between the lowest bass 

 and the highest soprano of ordinary voices 

 is three octaves. The human ear passes 

 in range from 32 to 33,768 vibrations per sec- 

 ond, or about eleven octaves, and it is inter- 

 esting to notice that the range of the human 

 voice occupies about the middle of that vast 

 range. It is said that some have been able 

 to hear tones produced by 40,000 vibrations 

 per second. The tone of the 32-foot organ 

 pipe is produced by about 32 vibrations per 

 second, while the highest tone of the organ, 

 that of the piccolo stop, is produced by about 

 4,000 vibrations per second. With reference 

 to these figures it is interesting to compare 

 the range of the human voice. 



138. Loudness or intensity depends on the 

 amplitude of the vibrations of the cords the 



