The_Complete_Idiot%27s_Guide_To_Music_Theory

Conversely, if you’re writing in F Major and throw a D♭ into your melody, that
note will sound out of place. Although it’s possible to use these nonscale (chromatic)
notes in a melody, it’s probably not something you, as a beginner, should
try. Composing a melody using chromatic notes requires a degree of harmonic
sophistication that seldom comes naturally—although it can be developed with
practice.
By the way, when you choose a scale for your melody, it doesn’t have to be a
major scale. Let’s say we’re still in the key of F, but you want to write a less lively,
more poignant-sounding melody. For this type of melody, you might choose to use
the D minor scale (which uses one flat, as with the key of F). When you write
this type of melody, you’ll probably center on the tonic triad of D minor (D, F,
and A) rather than the tonic triad of F Major (F, A, and C).
Use the Big Five
You can make things even simpler by sticking to five key notes within a given
major scale—the first, second, third, fifth, and sixth of the scale. (In C Major,
these notes are C, D, E, G, and A.)
These notes combine for what is called the pentatonic scale. (The word penta
means five; five tones equal a pentatonic scale.) By using only these five notes,
you avoid the two notes in the scale (the fourth and the seventh) that sometimes
create harmonic tension.
When you use the five notes in the pentatonic scale, it’s virtually impossible to
insert a “wrong” note into your melody. However, you can overuse these notes
and end up with a vaguely Oriental-sounding tune—or even something that
sounds a little bit like the theme to an old cowboy movie!
A melody based on the C pentatonic scale.
Find the Hook
For a melody to be truly memorable, there needs to be a piece of your melody
that really reaches out and grabs the listener’s attention. In pop music this is
called the hook, because it’s the part of the song that hooks the listener. In more
traditional music, this piece of the song is sometimes known as the motif (or
motive)—and is repeated throughout the entire piece of music.
A motif is typically fairly short—a few notes (think of the five whistling notes in
Sergio Leone’s theme from the movie The Good, the Bad and the Ugly) or, at
longest, one or two measures. When you hit on a good motif or hook, don’t be
afraid to use it—repeat it as often as you need, throughout your entire song.
Chapter 8: Melodies
99
Tip
Instead of basing
your melody on a
major or minor
scale, you can base
it on one of the modes—
Aeolian, Dorian, Lydian,
and so forth—discussed
back in Chapter 3.
Tip
On a piano, an
easy way to see
and play a pentatonic
scale is to
play strictly on the black
keys. These five keys—
G♭, A♭, B♭, D♭, and E♭—
comprise the G♭ pentatonic
scale.