TALKING ABOUT MUSIC 11the strings of a violin when set into motion by a bow. If you
could watch that string up close and in slow motion, you would
see that it vibrates, not in a simple back-and-forth oscillation,
but in a complex, sinuous motion. Acousticians analyze this
motion as the sum of a series of simple oscillations, known as
partials: the entire string length vibrating at one frequency,
the two halves of the string each vibrating at double that fre-
quency, the three thirds at triple that frequency, and so on.
The slowest frequency, that of the entire string length, has the
greatest amplitude and thus is by far the loudest, and it pro-
duces the pitch we perceive consciously: the fundamental
pitch. But the higher frequencies, called overtones, though
much softer, are present as well. The relative volumes of the
partials—the fundamental and its overtones, which together make up the tone’s
overtone series—can vary considerably, and it is this phenomenon that we hear
as timbre. The relative weakness of upper partials gives the fl ute its light timbre,
for example, whereas prominent upper partials give the oboe its plangent nasal-
ity. Thus we can say that timbre is how we perceive the details of an individual
tone’s overtone series.
With the voice, different vowel sounds correspond to different mixes of
partials—that is, different timbres. Try singing long notes on a single pitch
to the following vowels, with a breath after each: oo, oh, ah, eh, ee. With prac-
tice, you can hear the shifting of upper partials as you move from one vowel
to the next. Now try singing ah first in the normal way, then “through your
nose.” That nasal quality is the result of giving extra emphasis to the higher
partials of your voice. A slight nasality is a feature of much country sing-
ing, as can be heard in Dolly Parton’s “Coat of Many Colors” (LG 19.2). If you
compare her sound to Gladys Knight’s in “I Heard It through the Grapevine”
(LG 18.6), you can appreciate how vocal timbre can be a marker of different
musical genres.
Timbre exists because all musical tones (with the exception of electronically
generated sine waves) consist of multiple partials, related to one another by sim-
ple ratios: a fundamental frequency, a partial that vibrates twice as fast as the
fundamental, another that is three times as fast, another four times as fast, and
so on. Those simple numerical relationships not only govern the timbre of the
single tone but also affect how different tones relate to one another. With this
insight, we can take a closer look at the art of combining pitches.PITCHES IN COMBINATION: SCALES, KEYS, HARMONY
Scales
If we take all the pitches in a melody and arrange them in sequence from the
lowest to the highest (or vice versa), the resulting pitch collection is called a scale.
The term comes from the Italian word scala, a ladder or staircase, and the anal-
ogy is apt: each pitch may be visualized as a rung in the ladder, and a melody’s ris-
ing and falling contour as climbing up and down the ladder. Like actual ladders,
musical scales can have varying numbers of rungs, or scale degrees; unlike the
rungs of any good ladder, though, the degrees in most scales are not separatedK A diagram of a vibrating
string, illustrating the fi rst
six partials.172028_00b_001-017_INTRO_r3_ko.indd 11 23/01/13 9:47 AM