The 12 bar blues is the structure upon which blues music is built. It has been used since the inception of the genre and appears in almost every iconic blues song ever written. It provides the framework for the blues and will help you learn a wide variety of blues songs, as well as jam confidently with other musicians.
If you are new to playing the blues, then this Unit of Work will outline some of the key concepts you need to get started. It will cover the structure of the blues, some theory, and how you can apply this knowledge to your playing. After reading, you will be able to play the basic form of the 12 bar blues across a variety of different keys.
To understand what the I, IV and V chords are and their importance in blues, we need to delve into a little theory:
If you are new to playing the blues, then this Unit of Work will outline some of the key concepts you need to get started. It will cover the structure of the blues, some theory, and how you can apply this knowledge to your playing. After reading, you will be able to play the basic form of the 12 bar blues across a variety of different keys.
To understand what the I, IV and V chords are and their importance in blues, we need to delve into a little theory:
Keys, Scales & Chord Structures
Western music is based around ‘keys’. These keys refer to the scale that a piece of music is centred around. If as an example, someone says ‘this song is in the key of C’, they mean that the song is based around the notes of the C major scale.
Within the key of C (and all other keys in Western music), there are 7 notes. In the key of C, these notes are as follows:
Western music is based around ‘keys’. These keys refer to the scale that a piece of music is centred around. If as an example, someone says ‘this song is in the key of C’, they mean that the song is based around the notes of the C major scale.
Within the key of C (and all other keys in Western music), there are 7 notes. In the key of C, these notes are as follows:
C, D, E, F, G, A, B
A chord would be referred to as the I (one) chord. The key still features the same 7 notes that appear in the key of C, but the starting point is different.
Each of those notes has a corresponding number, which alters depending on the key that you are in.
In the key of C for example, the note of C is marked as 1. D is marked as 2, E is marked as 3, and so on. And in any key, the starting note – which is C in this case – is often referred to as the root note or tonic note.
Chords within a key are marked out in much the same way as the notes. The key difference is that chords are referred to using Roman numerals. So in the key of C major, the note of C would be marked as 1, and the chord of C would be marked as I. If it is minor, you use the lover case 'i'.
If we were to switch to the key of A, the pattern of notes and chords would stay the same, but the specific notes and chords would change. So A would be note 1, and an
The I, IV & V Chords
Let’s apply these ideas to our 12 bar blues structure. We know that in the key of C, the notes of the scale are as follows:
Each of those notes has a corresponding number, which alters depending on the key that you are in.
In the key of C for example, the note of C is marked as 1. D is marked as 2, E is marked as 3, and so on. And in any key, the starting note – which is C in this case – is often referred to as the root note or tonic note.
Chords within a key are marked out in much the same way as the notes. The key difference is that chords are referred to using Roman numerals. So in the key of C major, the note of C would be marked as 1, and the chord of C would be marked as I. If it is minor, you use the lover case 'i'.
If we were to switch to the key of A, the pattern of notes and chords would stay the same, but the specific notes and chords would change. So A would be note 1, and an
The I, IV & V Chords
Let’s apply these ideas to our 12 bar blues structure. We know that in the key of C, the notes of the scale are as follows:
C, D, E, F, G, A, B
C is the root note and is marked as 1. F is the 4th note in the scale and G is the 5th. As mentioned above, chords within a key follow the same pattern. The only difference is that they are marked with Roman numerals, rather than numbers. From here then, we can see that in the key of C – the I, IV and V chords are as follows:
C F G
(I) (IV) (V)
See the video below for how to play the 12-Bar Blues in C
(I) (IV) (V)
See the video below for how to play the 12-Bar Blues in C
The amazing thing, is that you can apply this idea to any key. You just need to count up from the root note of the key. So if someone tells you that a song is in the key of A, all you need to do is map out the notes of the A major scale, and then pick out the I, IV and V chords from there. In the A major scale, the notes are as follows:
A, B, C#, D, E, F#, G#
Looking at the key of A then, we can see that the I, IV and V chords are as follows:
A D E
(I) (IV) (V)
(I) (IV) (V)
You can apply this formula to any key. If as an example you know that a blues song is in the key of D and it also follows the 12 bar progression, you can work out which chords will appear in the song by mapping out the notes of the scale and picking the I, IV and V chords from there.
The Pattern of the 12 Bar Blues
Now we know the structure of the 12 bar blues and how to apply it to different keys, we need to learn how the I, IV and V chords fit together within the progression. Luckily, this is nice and easy.
The 12 bar blues is easiest to understand if you break it down into 3 sections – each one 4 bars long.
The first 4 bars run as follows:
Now we know the structure of the 12 bar blues and how to apply it to different keys, we need to learn how the I, IV and V chords fit together within the progression. Luckily, this is nice and easy.
The 12 bar blues is easiest to understand if you break it down into 3 sections – each one 4 bars long.
The first 4 bars run as follows:
I, I, I, I
In the second 4 bars, there is the introduction of the IV chord, and the 4 bars run like this:
IV, IV, I, I
In the final – and most interesting section of the progression – there is the introduction of the V chord:
V, IV, I, I
This final section of the 12 bar blues is also called the ‘turn around’, because it concludes the 12 bar progression and takes you back to the start.
Written out like this, the progression just looks like a collection of random numerals. But when we put all of the pieces together, the progression (hopefully!) becomes much clearer:
Written out like this, the progression just looks like a collection of random numerals. But when we put all of the pieces together, the progression (hopefully!) becomes much clearer:
Here is a minor version of the same progression:
Let's see if you can apply this new Blues knowledge!