Chord Progressions

Chord Progressions are a series of chords used for the rhythm of a song. These chords sound good to the ear because the follow a set of musical rules. Sometimes it is by accident, and sometimes it is by design, but most western music compositions use chord progressions in specific keys. Let’s examine the theory a little more closely.

Roman numerals are used to indicate the positions in a scale. In reference to chord progressions, uppercase roman numerals indicate the primary chords, the lowercase numeral are secondary chords.

• I - Tonic - Degree is major
• ii - Supertonic - Degree is minor
• iii - Mediant - Degree is minor
• IV - Subdominant - Degree is major
• V - Dominant - Degree is major
• vi - Submediant - Degree is minor
• vii - Leading Tone - Degree is diminished

Here is the C Major scale with its scale positions, along with the chords used in the key of C

The most common chord progression is I, IV, V. This is also called the 'Blues Progression'. This is the chord progression we will use in this lesson, and is used in rock and blues music. This means that when a song is played in the key of C, a basic chord progression using C, F and G chords will be used. Here are some different keys using the blues progression.

If you know the key of the song, you can use the I,IV,V chords of that key. Now, lets apply what we have learned with some simple exercises:

1. Strum I, IV and V two times each 
2. Strum I, IV and V four times each
3. Strum I four times, strum IV two times and strum V two times
4. Strum I four times, strum IV two times and strum V four times
5. Use various strumming patterns using these 3 chords.

Sometimes you will see exercises like those above are written this way:

A / A / A / A
D / D / A / A
E / D / A / E

This is blues progression in the key of A.

Other Progressions:

There are also other progressions we can use. We focused on the blues progression because of it is commonly used in rock music, but there are progressions that are used primarily in jazz music as well. Here are a few commonly used chord progressions.

• I7, IV7, V7
• I, iim, IV, V
• IV, I, IV, V

For an exercise, use the graph above to figure out the chord used for various keys. The key of C is the easiest to figure out, the key of G is the most common, so try using these keys.

Being able to play in different keys helps when improvising or 'sitting in' with other musicians as well as in writing songs. Knowing which key the song is in can help you determine which scale(s) to use when composing solos and licks (see the Major Scale lesson). Unless you know how to read music, you may need to listen to the song to determine which key it is in, but sometimes its as easy as knowing what the first chord is. This is often (but not always) the key.

This is just a basic introduction into Chord Progressions, but it should be enough to get you started on your own. As always, good luck!