Blues music is the bedrock of much of today’s popular music. For guitarists, understanding blues is essential. It not only opens up a rich musical landscape but also provides a common language for jamming and collaborating with other musicians. If you’re just starting your guitar journey and thinking “I will learn guitar chords,” then the blues is a fantastic place to begin.
While the blues has depths that can occupy musicians for a lifetime, the foundational structures are surprisingly accessible. The complexity often lies in the feel and nuanced expression, but grasping the basic chord structures is straightforward.
This guide is designed for beginner guitarists. We’ll assume you’re new to chords and scales, and we’ll keep everything as simple as possible. Our aim is to equip you with the fundamental knowledge to start playing blues guitar and confidently say, “I will play guitar chords in a blues song!”
Unlocking the 12 Bar Blues Chord Progression
The cornerstone of blues music is the 12 bar blues chord progression. Everything in blues guitar playing revolves around this structure, making it the perfect starting point.
This progression uses just three chords and spans 12 measures, or bars. A measure is a unit of musical time, typically containing 4 beats in blues. The specific chords used will depend on the key of the song.
Most blues songs are built upon repetitions of this 12 bar progression. Melodies, vocals, and guitar solos unfold over this repeating chord structure.
Let’s look at the 12 bar blues progression in the key of E as an example:
As you can see, the progression in E uses three chords: E7, A7, and B7. These are Dominant 7th Chords, indicated by the “7” in their name. Dominant 7th chords have a distinctive, bluesy, and somewhat edgy sound. They are very common in blues progressions. If these chords are new to you, here are simple ways to play them:
To play the progression, you simply need a 4-beat strumming pattern for each measure. The rhythmic possibilities are vast, and experimenting with different strumming patterns is part of the fun.
Transposing the Blues: Chord Progressions in Different Keys
Learning to play the blues in different keys is crucial. The 12 bar blues progression isn’t limited to the key of E; you can play it in any key. To understand how, we need to delve into some basic music theory.
Every key has a set of seven core chords. In music theory, these chords are numbered using Roman numerals I through vii. The blues progression utilizes the I, IV, and V chords of any given key. In the key of E, E7 is the I chord, A7 is the IV chord, and B7 is the V chord. Notice that the I chord always shares the same root note as the key itself (E in the key of E).
The IV and V chords maintain a consistent relationship to the I chord, regardless of the key. This relationship is easily visualized on the guitar fretboard. If you locate the root note of your I chord on the 6th string, the root notes for the IV and V chords will always be in the same relative positions:
To use this effectively, you’ll need to know the notes on your guitar’s 6th and 5th strings. This is valuable knowledge for any guitarist, especially beginners. Here’s a fretboard diagram as a reference:
Once you’re familiar with the notes, finding the IV and V chords becomes straightforward. Locate the root of your I chord on the 6th string. Then, the roots of the IV and V chords are positioned directly below it on the fretboard as illustrated. For our E blues example, the open 6th string is E (I chord). The open 5th string is A (IV chord, directly below). Moving up two frets from A on the 5th string lands you on B (V chord). Turning these root notes into Dominant 7th chords gives us E7, A7, and B7.
Let’s take another key, G, as an example. To play the blues progression in G, we first find the G note on the 6th string. This is at the 3rd fret. This is our I chord root. Following the fretboard pattern, the IV chord root is on the same fret, but on the 5th string, which is a C note. Moving up two frets from C on the 5th string gives us a D note, the root of our V chord.
So, in the key of G: I = G, IV = C, and V = D. Converting these to Dominant 7th chords, we get G7, C7, and D7.
Now we arrange these chords into the 12 bar blues structure. Referring back to the E blues progression and using Roman numerals for chord positions:
This is the universal formula for the 12 bar blues. Let’s apply our G7, C7, and D7 chords:
And there you have it – the 12 bar blues progression in G! You can now apply this process to discover the blues progression in any key:
- Find the root note of your I chord on the 6th string.
- Locate the roots of the IV and V chords based on the I chord root position.
- Transform these root notes into Dominant 7th chords.
- Arrange the chords using the 12 bar blues formula.
Exploring Common Blues Progression Variations
While the standard 12 bar blues is fundamental, blues music is rich with variations. Within a single blues song, the progression usually remains consistent throughout. However, different songs often employ slight variations of the basic structure. Here are a few common ones to know.
A simplified version, often used in faster blues rock, omits the IV chord in the 10th measure, replacing it with another measure of the V chord. Also, the final V chord in the 12th measure is replaced by the I chord. This creates a more driving feel:
Another common variation is the ‘quick change,’ where the IV chord appears in the 2nd measure instead of staying on the I chord for the first four measures:
Finally, there’s a variation with more chord changes in the last two measures. In the 11th measure, the I chord is played for the first two beats, followed by the IV chord for the last two beats. The 12th measure then uses the I chord for the first two beats and the V chord for the last two. This variation, sometimes combined with the ‘quick change’, is frequently heard in slower blues:
This covers the basics of constructing and understanding the 12 bar blues progression and “I Will Guitar Chords” within it. In the next installment of this series, we’ll explore the blues scale, its essential patterns, and how to use it across the guitar neck in different keys. Future articles will delve into blues turnarounds, riffs to replace chords, and classic blues standards.
SRV Photo credit: Joe Bielawa / Foter / CC BY
