494: 



MOVEMENTS VOICE AND SPEECH. 



256 



Soprano. 



1024 



128 



Tenor. 



512 



The accompanying figures indicate the number of vibrations per second in the corresponding tone. It 

 is evident that from c' to /' is common to all voices ; nevertheless, they have a different timbre. 

 The lowest note or tone, which, however, is only occasionally sung by bass singers, is the contra-F, 

 with 42 vibrations ; the highest note of the soprano voice is a"', with 1,708 vibrations (Landois and 

 Stirling). 



There is really no great difference in the mechanism of the different kinds 

 of voice, and the differences in pitch are due chiefly to the greater length of 

 the vocal chords in the low-pitched voices and to their shortness in the higher 

 voices. The differences in quality are due to peculiarities in the conforma- 

 tion of the larynx, to differences in its size and to variations in the size and 

 form of the auxiliary resonant cavities. Great changes in the quality of the 

 voice may be effected by practice. A cultivated note, for example, has an 

 entirely different sound from a harsh, irregular vibration ; and by practice, 

 a tenor may imitate the quality of the bass, and vice versa, although the 

 effort is unnatural. It is not at all unusual to hear male singers imitate very 

 closely the notes of the female, and the contralto will sometimes imitate the 

 voice of the tenor in a surprisingly natural manner. 



Action of the Intrinsic Muscles of the Larynx in Phonation. In the 

 production of low chest-notes, in which the vocal chords are elongated and 

 are at the minimum of tension that will allow of regular vibrations, the crico- 

 thyroid muscles are undoubtedly brought into action, and these are assisted 

 by the arytenoid and the lateral crico-arytenoids, which combine to fix the 

 posterior attachments of the vibrating ligaments. It will be remembered 

 that the crico-thyroids, by approximating the cricoid and thyroid cartilages 

 in front, increase the distance between the arytenoid cartilages and the an- 

 terior attachment of the vocal chords. 



As the notes produced by the larynx become higher in pitch, the pos- 

 terior attachments of the chords are approximated, and at this time the lat- 

 eral crico-arytenoids are probably brought into vigorous action. 



The uses of the thyro-arytenoids are more complex ; and it is probably in 

 great part by the action of these muscles that the varied and delicate modi- 

 fications in the rigidity of the vocal chords are produced. 



The differences in singers as regards the purity of their notes are due in 

 part to the accuracy with which some put the vocal chords upon the stretch ; 

 while in those in whom the voice is of inferior quality, the action of the 

 muscles is more or less vacillating and the tension is frequently incorrect. 



