The Complete Idiot''s Guide to Music Theory

Part 3:
Tunes
140
Old Johann was able to wring the most out of a very simple chord progression;
in this case nothing more than I-IV-I-IV-I-V-I. Of course, this shows that you
don’t need a complex chord progression to create great music.
Dvorˇák’s 
New World Symphony
Dvorˇák’s 
New World Symphony
uses another relatively simple chord progression,
as you can see here:
The chords to Dvorˇák’s 
New World Symphony.
The chord progression is basically I-V-I, with a neat little ii-V-I imperfect
cadence at the end. There’s also a very unique nonscale twist in the second half
of the third measure, where the I chord (D
) suddenly gets a raised fifth and
goes augmented. (In the orchestral score, the fifth is in the bass in this measure,
for a very dramatic effect.) The use of the augmented tonic sets up an unex-
pected tension, without messing up the harmonic structure by throwing in
something like a IV or a V chord where it wouldn’t really belong.
Pachelbel’s 
Canon in D
Even more simple is the chord progression behind Pachelbel’s 
Canon in D
, as
you can see here:
The chords to Pachelbel’s 
Canon in D.
Note how the chords flow, one into the next, based on established chord leading
rules—I-V-vi-iii-IV-I-IV-V—and then back to the I, again and again. You can
play this progression all night long and not get tired of it; that’s what makes it
such a classic.

---

Chapter 10:
Chord Progressions
Mary Had a Little Lamb
Finally, let’s figure out the chords to “Mary Had a Little Lamb.” Just as the melody
is a simple one, so is the accompanying chord progression—nothing more than
I-V-I, repeated once. Sometimes the simplest progressions are the best!
141
The chords to “Mary Had a Little Lamb.”
Chord Writing Tips
When it comes to fitting a chord progression to an existing melody, here are
some tips to keep in mind:
◆
Try some common chord changes first. You’d be surprised how many
melodies fit with the I-IV-V progression!
◆
The main notes in the melody (typically the notes that fall on the first and
third beats of a measure) are the first, third, or fifth note of the underlying
chord.
◆
Try to simplify the melody by cutting out the passing and neighboring
tones (typically the shorter notes, or the notes not on major beats); the
main notes you have left often will suggest the underlying chord.
◆
Make sure you’re in the right key. In most cases, the “home” note in the
melody is the tonic note of the underlying key.
◆
Generally, the slower the tempo, the more frequent the chord changes.
(So if you have a long whole note, or a note held over several measures,
expect to find several different chords played behind that single note.)
◆
Work backward from the end of a melodic phrase, remembering that
melodies almost always end on the I chord. You then can figure out the
cadence leading to the I, and have half the song decoded fairly quickly.
◆
Chord changes generally fit within the measure structure, which means
you’re likely to see new chords introduced on either the first or third beat
of a measure.

---