12-Bar Blues
When musicians who have never met before get together to play they might come from wildly various musical backgrounds, age groups, and cultural backgrounds, but there is one progression that transcends all these barriers and unites musicians everywhere — the 12-bar blues progression. That's because the 12-bar blues progression is so elemental that most musicians, regardless of their age, background, or level of proficiency, know it — so you need to know it too.
The 12-bar blues progression, like all chord progressions, is based on the notes of the scale of the key the progression is in. The chords, like the individual notes of the scale, are also known as scale degrees, and they are often indicated in music with Roman numerals. For example, if you're playing a blues in G, the scale degrees would be:
The 12-bar blues progression is the same as the 1-4-5 progression mentioned above, the 1, 4, and 5 referring to the scale degrees I, IV, and V.
The classic “wah” sound you hear often in harmonica music is created by cupping your hands tightly around the back of the harmonica and then opening the cup you've made. This effect can be used slowly to create a long wah, or it can be done quickly and repeatedly to create a tremolo sound.
The first degree of the scale is called the tonic, while the fourth degree of the scale is called the subdominant, and the fifth degree is called the dominant.
Here's how the basic 12-bar blues progression goes:
4 bars of tonic I
2 bars of subdominant IV
2 bars of tonic I
1 bar of dominant V
1 bar of subdominant IV
2 bars of tonic I OR 1 bar of tonic I and 1 bar of dominant V
There are other variations of the 12-bar blues progression, including:
1 bar of tonic I
1 bar of subdominant IV
2 bars of tonic I
2 bars of subdominant IV
2 bars of tonic I
1 bar of dominant V
1 bar of subdominant IV
2 bars of tonic I OR 1 bar of tonic I and 1 bar of dominant V
and
4 bars of tonic I
2 bars of subdominant IV
2 bars of tonic I
2 bars of dominant V
2 bars of tonic I
12-bar blues progressions also come in minor keys. The chords appear in the same order and for the same duration as blues in a major key, except that in this case the chords are all minor.
Here's an example of a 12-bar blues progression. It's a slow blues feel in the key of G.
FIGURE 11-2: Slow blues in G
TRACK 37
Here's an example of a 12-bar blues shuffle.
FIGURE 11-3: Blues shuffle in G
TRACK 38
Here's a 12-bar blues in the 1-4-5 progression, only with more of a jazzy feel.
FIGURE 11-4: Jazzy blues in G
TRACK 39
