There has always been a controversy over the issue of writing a melody first or a chord progression first or both simultaneously. Ultimately, good writers create the melody and the chord progression co dependently, But when you’re beginning to write, it’s generally more effective to cut down the variables but focusing on melody or on a chord progression first.
In my teaching, I’ve always found that a good chord progression leads to melody more easily than a good melody leads to a chord progression. Since this process is a personal art form, everyone responds individually to the order of the elements. A purely melodic instrument such as a sax or trumpet often finds first inspiration in melody. On the other hand, a chord instrument such as guitar or piano, may choose the chord route to get started.
Regardless of this, the first issue is form. Form is the structure of a composition in regards to the length of the themes, the time signature, the number of themes and the order of themes. Most songs traditionally are based on 8 bar themes or if blues oriented, on 12 bar themes.
We’ll focus initially on 8 bar themes. The majority of songs are binary which is to say that they have 2 themes. Let’s call the first theme A and the second theme B. The most common orders of these themes are AABA, AAB or AABB.
Our first job is to choose a major key or a minor key. Major keys will generally produce a brighter piece. Minor keys produce a darker piece. We”ll arbitrarily pick the chord progression approach first.
Let’s start in one key and let’s make it C major. The chords that you need to use to keep your piece in C major are the following. In three part harmony, they are C, Dm, Em. F, G, Am and Bdim. In four part, they would be Cmaj7, Dm7, Em7, Fmaj7, G7, Am7, and B half dim 7. Identify these chords as the I, II, III, IV, V, VI and VII chords. This becomes a convenient approach when we begin to change keys.
The I, III and VI chords are considered passive chords which is to say that they are at rest. The remaining chords V, IV, II and VII are active chords which is to say that they are restless. The very important term resolution is the effect generated by any active chord moving to any passive chord.
Chord progressions need to move in and out of these states of active and passive to create and to maintain interest.
The first exercise is to experiment with and listen to the effects of active and passive chords. Play a I, then a V and then return to the I. You’ll notice how satisfying the movement of V is back to I. Clearly, the I chord is the center of the key and the most passive or grounded. The V is its opposite – the most active and restless chord in the key.
Try one active chord to one passive chord, Then try two active chords to one passive chord. Continue trying combinations as you increase your awareness and sensitivity to the effects of resolution.