12 Bar Blues Explained
The 12 bar blues is a song form. It is not only heard in blues style music. We hear this song form in rock, jazz and country. Understanding the structure of the 12 bar blues will lead you to learning thousands of songs. Here is what you need to learn.
12 Bar Blues Form
The title refers to the length of the song structure. There are 12 bars of music that repeat several times to create the song. Certain chords are used from the scale within the 12 bar blues. We selected the first chord (I), fourth chord (IV) and five (V) chord from a scale or key. To understand more about scales visit our articles explaining how they are created.
We can use major or minor scales or key. The I, IV and V chords are then used in particular bars. See below for how to place these chords in the song.
We use the roman numerals to avoid assigning a specific key to the example. If we were to select a key, like A major, the chords in each bar would look like this.
You can play this on any instrument. The chord sequence also influences the melody part such as the singing or guitar solos.
12 Bar Blues Use in Songs
Songwriters may use the 12 bar blues directly as written. Here is an example of direct use of the 12 bar blues in a song.
They may choose to use the form in just a verse or chorus. The band U2 used the 12 bar structure for the verses of their enormous hit “I Still Haven’t Found What I’m Looking For”. This is not a song that listeners would associate the 12 bar blues song form with.
Some composers have used the first 8 bars of the song structure. I see this commonly in songs based in guitar riffs. The song “Sunshine of Your Love” by Cream, best known for guitarist Eric Clapton, uses the first eight bars to shape how many times to play each riff. This is one of the first songs I teach to guitar students.