What Is Blues?The twelve bar blues is a very common chord progression found in a lot of songs. The progression, whilst less popular now, is very common in early blues music around the '60s era, with it being common in many Elvis singles. Even today, many songs sample parts from or even predominantly use the twelve bar blues.
Important - be careful with time signatures. This can alter when you play in the bar.
How Does It Work?The concept is simple - once you get your head around it! Songs composed using the twelve bar blues typically have just three chords - all being major. The most common way to describe the progression is with this chart below:
I I I I
IV IV I I
V V I I
This works quite simply. Choose any major scale. For the purposes of this, I'll choose E major. The first chord in E major is - of course - E major. You can list the chords in the scale, but you only really need three.
I E Major
II F# Minor
III G# Minor
IV A Major
V B Major
VI C# Minor
VII D# Diminished
Pay attention to chords one, four and five - E, A and B. Those are your chords for the simple twelve bar blues - nothing else!
Here's the playing order:
Bar 1 2 3 4
Chord I I I I|I I I I|I I I I|I I I I|
There you have it - the simple twelve bar blues!
Bar 5 6 7 8
Chord IV IV IV IV|IV IV IV IV|I I I I|I I I I|
Bar 9 10 11 12
Chord V V V V|V* V* V* V*|I I I I|I I I I|
In bar ten, you can either switch back to IV or you can continue playing V. Many modern variations switch back to IV, though the classic style is to continue with V.
The example I've given you - in the key of E major - is the chord sequence in the classic "Steamroller Blues"! However, say you wanted to do it in D major, or even F# major - you'd just follow the steps above, and it would work!
Once you get the hang of it, you can use this to write any blues-y type number or try to play blues songs you struggled with before.
To jazz it up:
For more experienced players, if you can grasp the jazzy time-playing of the song, you should throw some seventh chords into the blues. Don't throw in a random seventh - take the chord you would play and just seventh it! When playing, listen out for when you think a seventh should be used. Usually it's on the last beat of the bar, but your song may differ!
Got all that? Good luck!