The Nuts and Bolts of Music - Part Three: Harmony |
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n our first article dealing with the basic musical elements--rhythm, melody, harmony, form, dynamics and texture--we talked about what is probably the most instinctive or "primitive" element of all: rhythm. Our second article, Melody, was concerned with single notes that are strung together "horizontally", as it were, to make a purposeful line or tune; melody is, in fact, often called the horizontal element of music. In the present article we are concerned with notes that are placed together "vertically" in simultaneous groups, or chords, so that they sound together as a blend.
This article includes musical illustrations in MIDI sound; to hear
them, click on each example separately as you come to it. The linked
musical examples will open in a separate tab or window.
What is a Chord?
A chord is a group of three or more tones that make an acceptable combination when heard together, and right away we're getting into muddy water because the qualifier "acceptable" has a pesky habit of changing its meaning every time you consider the music of a different era or culture. Many chords that were used by Beethoven would have been utterly unacceptable to, say, a medieval monk, while the great German master himself would have been perplexed (though probably intrigued) by a lot of the chords invented by Debussy. Again, much traditional music of Africa and the Orient doesn't use chords in our sense of the term at all. So for this article we will talk mostly about the good old-fashioned "traditional" chords that we hear in Happy Birthday, The Star-Spangled Banner and the like.
Harmony
Harmony is simply the mix of sound that is produced by the ongoing series of chords that make up a musical composition as it progresses. Harmony always refers to simultaneous sounds, while melody alludes to single tones that are successive. The chords which make up the beginning of America look and sound something like this [Ex. 1]:
What you're hearing is the harmony by itself, without the familiar melody on top. Using spatial metaphors to describe sound is always limited, but just from the arrangement of notes on the page it is easy to see why harmony is called the vertical element of music. Any composition that is more than just an unaccompanied melody will make a blend of sounds that are both simultaneous (vertical) and successive (horizontal)--melody and harmony working together throughout, like the interlocked alignment of the words in a crossword puzzle.
Very often harmony results
indirectly from the combining of separate melodies
[Ex.
2]:
That's right: Dixie and Yankee Doodle played together--who said the North and South couldn't get along?
Counterpoint
Example 2 is an illustration of what we call counterpoint, which means the combination of independent melody lines, but at any point we could stop and compare two simultaneous tones in their "vertical" relationship, to hear how they blend together--or, in other words, listen to the harmony they produce. In fact, this is precisely the way harmony developed in the first place, a whole millenium ago: melodies were sung or played by themselves without any harmony at all; then people would sing them together, first at the same pitch but later at different pitches--a tune moving along at two different pitch levels, like railroad tracks--and eventually the two lines began to diverge and became more and more independent, both in notes and in rhythm. Pretty soon additional melody lines were added to the mix, and at any given point you had the blend of sounds we call harmony--but the blend was arrived at horizontally, almost by default. Ultimately, it became commonplace to compose harmony simply by stacking notes on top of one another, without the help of multiple melodies.Cadences
How does a composer decide what chords to write? In the previous article, Melody, we ended with a brief description of cadences. A cadence is something like a period at the end of a sentence--a place where the music feels as though it has arrived at a chord that sounds like "home"--and the last audio example of that article demonstrated what a familiar song would sound like without it; let's hear it again [Ex. 3]: Now, why do certain chords give us the feeling that the music wants to arrive there and stop? The answer lies in the raw material the composer uses for his chords, and that material is found in a scale.Scales and Keys
Most familiar music of our culture is said to be written "in a key", and to be in a key means to be confined to a set of related chords, one of which conveys the feeling of being a home base to which the others want to gravitate. Where do the tones of these chords come from, and why does one chord sound like a resting place? They come from a particular scale--a series of eight adjacent tones arranged in order of pitch.The most commonly used scales are major [Ex. 4]:
. . . and minor, which is the same except that the third and sixth tones are lowered [Ex. 5]:
Example 4 is the scale of C Major, and note that the top and bottom tones (both C's) sound like arrival points, or "home". In fact, both scales (the other one is C Minor) have this characteristic, which is caused by the fact that the neighboring tones are not all the same distance apart. A scale provides the tones for the chords of a key in exactly the same way that the twenty-six letters of the alphabet provide the letters for all the tens of thousands of words in the English language. To be in a key, then, means to be in a scale, so if we were to play Happy Birthday in the key of C Major we would construct its chords from the tones of that scale [Ex. 6]:
.....and the final chord sounds like "home" because it's built on the tone that is the arrival point of the scale.
What would happen if we constructed the chords of Happy Birthday from the scale of C Minor? [Ex. 7]:
Maybe that's the way we feel like singing it when we get older! When you use a minor scale, you come out with a minor key.
Harmonic Variety
Composers are not, of course, bound to use only the tones of the scale they happen to be in at the time. Other tones lie between the eight degrees of the regular scale and, though not a part of it, combine to provide a total of twelve different pitches available within the scale's range. These can be used in a great variety of ways, not only to add richness to or between the regular chords of the key, but to provide the material for the building of scales on other pitches as well, giving us a total of twelve major and twelve minor scales. Thus music can be composed in any of 24 different keys.
Stay Tuned!
Next time we will tackle the subject of form in music, describing some of the basic structures. Hope you'll be back!Last updated: 02/02/24