c. Timbre of Sound. The third characteristic of sound is called timbre, sometimes called quality, is vital to the
recognition of sounds and voices. A note played on a violin is recognized as coming from a violin; a note coming from a
flute is recognized as coming from that instrument because of the particular combination of harmonics contained in the
sound as previously explained. The rest depends on the frequencies and intensities of the harmonics of the sound, relative
to the fundamental frequencies. A particularly pleasing voice or sound is generally rich in overtones. To any individual,
the timbre or quality of a particular sound may or may not be pleasant, but the quality helps to identify the object,
instrument or person that is its source.
Characteristics of Speech.
a. Human speech contains all of the basic characteristics of sound plus some peculiarities of its own. The vocal
cords are the source in the production of most vocal sounds. They are vibrated by a stream of air from the lungs being
forced between them. The pitch of a violin is determined by varying the length and thickness of its strings. The range and
pitch of the voice is determined in much the same way. The vocal cords become shorter and thicker or longer and thinner
while speaking. The amount of air (power) furnished by the lungs determines the loudness of volume of the sound
produced. You can recognize the difference in the amount of effort required between a shout and a whisper. The action
of the lungs when generating power is similar to the compressive action required to play an accordian.
b. The throat, mouth, and nasal passages contribute to the quality of the sound produced by the voice. The size
and shape of the vocal passage is varied by the size and shape of the tongue, palate, lips, and jaw which determines the
number and proportions of the various harmonic frequencies in the resulting sound. The upper nasal cavity and the bone
structure of the head also have an effect on the timbre of the voice. The effect from the actions of these organs can be
compared to the various sizes, shapes, and materials, and these effects on the quality/timbre of the musical sounds
produced by various wind instruments.