What is 12-Bar Blues

12-bar blues is one of the most popular chord progressions in blues music. You’ll also hear it in rock and roll, jazz, R&B, country, folk, and other styles that have roots in the blues. It’s been around since the early 1900s and is the basis for thousands of songs.

Characteristics

A 12-bar blues has a distinct form made up of three four-bar lines. You count those 4 + 4 + 4 bars and get 12 bars total. Chord-wise, it goes like this:

• The first four bars are played in the tonic (I) chord
• The second four bars switch between the subdominant (IV) chord and the tonic (I)
• The last four bars move from the dominant (V) chord back to the tonic (I)

In the key of E, the chords would be E (I), A (IV), and B (V). There are variations on this, but that’s your basic structure.

The Feel

When you listen to a 12-bar blues, you’ll notice a couple of things right away. The tempo is usually around 40–60 beats per minute. It has a kind of sway to it. You can tap your foot or nod your head in time real easy.

Lyrically, 12-bar blues songs tend to follow an AAB pattern. The first line gets repeated and then there’s a different third line that often rhymes:

I woke up this morning I woke up this morning
The blues was ’round my bed

You also get a lot of call and response between the lead singer and the instruments or other vocalists. This goes back to the blues’ roots in African music.

Guitarists and 12-Bar Blues

Most people probably think of the blues as guitar-based music. Early blues musicians often couldn’t afford guitars, so they’d play a lot of slide guitar on makeshift one-string instruments called diddley bows. Guitar became central as the blues evolved.

Guitarists use 12-bar blues chord progressions for both rhythm and soloing. During the solo breaks, lead guitarists will use the pentatonic scale and really put some feeling into their string bends and vibratos. B.B. King, Buddy Guy, and Stevie Ray Vaughan are some of the most famous guitarists known for their 12-bar blues playing.

Endless Variation, Universal Appeal

Although there’s a very defined structure, you’ll never hear two 12-bar blues songs that sound exactly the same. Artists take that foundation and make it their own. The variations are endless.

You might think something so formulaic would get boring, but it never does. There’s a reason 12-bar blues has been around for over a hundred years and is still going strong. It just works, and it works in a way that lets musicians express themselves while still connecting to the audience. We respond to it on a basic level.

When you break it down, 12-bar blues is really a musical conversation. The lyrics tell a story, the instruments “talk” to each other, and we get to listen in. It feels like the most natural thing in the world. And no matter how far modern music seems to stray, it always circles back home to the blues.