Blues Chord Substitution: Add Color to Your Blues Chords

You’ve learned how to play dominant 7th chords and how to use them in the I-IV-V progression. That’s the foundation. But if you want your blues to sound more sophisticated—more colorful—you need to understand chord substitution. It’s about adding notes to basic chords to change their flavor without losing their function in the progression.

This is part 3 of our blues chords series, and today we’re talking about how to embellish your blues chords by adding 6ths, 9ths, and other extensions. These substitutions add color and interest without changing what the chord is doing in the song.

What Is Chord Substitution?

Chord substitution means replacing a basic chord with a more complex version of the same chord. You’re not changing the chord’s role in the progression—you’re just adding extra notes to make it sound richer or more interesting.

For example, instead of playing a plain A chord, you might play A6 or A9. Instead of a basic A7, you might play A7♯9 or A13. The chord is still functioning as an A chord in the progression, but it has more color.

This is everywhere in blues. Listen to any blues recording by B.B. King, Stevie Ray Vaughan, or Robert Cray, and you’ll hear these embellished chords. They’re what makes blues sound sophisticated instead of just three basic chords.

Adding the 6th

The simplest substitution is adding a 6th to a major chord. Take a basic A chord. If you add the 6th—which is the note F#—you get an A6 chord. It’s a small change, but it makes the chord sound sweeter and more colorful.

You can play A6 in open position by keeping your regular A chord shape and adding your pinky on the second fret of the high E string. That F# is the 6th, and it changes the whole feel of the chord.

The 6th works great as a turnaround chord or as a passing chord. You’ll hear it at the end of a 12 bar blues all the time—it gives you that classic resolution sound without going back to a plain major chord.

The Dominant 9th Chord

Now we’re getting into dominant chord extensions. A dominant 9th chord is a dominant 7th chord with an extra note—the 9th—added on top. It’s got more tension than a plain 7th chord, and it sounds jazzier.

The A9 chord shown here is a common voicing you’ll use all over blues and jazz. It’s moveable, so once you’ve got the shape, you can transpose it to any key. This voicing has a rich, full sound that works great in a blues progression.

You don’t have to understand the theory to use these chords. Just learn the shapes and hear how they sound different from plain 7th chords. The 9th adds a little bit of sweetness and complexity.

The 7♯9 Chord (The Hendrix Chord)

This is the famous “Hendrix chord”—a dominant 7th with a sharp 9th. It’s got a bluesy, almost dissonant sound that creates tension. Jimi Hendrix used it constantly, but it shows up in blues all the time, especially as a turnaround or ending chord.

The E7♯9 chord in open position is easy to grab. You’re basically playing an open E7 and adding your pinky on the second fret of the high E string. That raised 9th—the G note—is what gives it that distinctive, slightly nasty sound.

Don’t be afraid of the dissonance. That’s part of the blues. The 7♯9 chord doesn’t resolve the way a major chord does—it keeps you hanging, which is exactly what you want at the end of a phrase.

The 13th Chord

The 13th chord is as far as you can stack extensions on a dominant chord. It includes the 7th, 9th, 11th, and 13th all at once. You can’t play every note on a guitar—there aren’t enough strings—so most 13th chord voicings leave out a few notes. But you still get that full, sophisticated sound.

This A13 voicing is one of the most common. It’s a bar chord shape that you can move up and down the neck. It’s rich and complex without being muddy, and it fits perfectly into a blues progression.

13th chords work great as substitutes for plain dominant 7th chords. Any time you’ve got a 7th chord in a progression, you can usually swap in a 13th chord and it’ll sound more sophisticated.

Minor Chord Variations

You can also embellish minor chords. Instead of a plain Am, you can play Am7. Instead of Am7, you can play Am9 or Am11. Each extension adds a different flavor.

Minor 7th chords are everywhere in blues and jazz. They’re mellow and smooth, and they fit perfectly into minor blues progressions. This Am7 voicing is a bar chord shape that works in any position on the neck.

The difference between a plain minor chord and a minor 7th is subtle, but it’s there. The m7 sounds more sophisticated and less definitive. It’s perfect when you want a chord that doesn’t resolve too strongly.

When to Use These Substitutions

You don’t need to use these chords everywhere. Sometimes a plain 7th chord is exactly what you want. But when you’re looking for more color or sophistication, these substitutions give you options.

A good rule: use plain chords when you want clarity and drive, and use substitutions when you want color and sophistication. In a fast shuffle, stick with basic 7th chords. In a slow blues, try substituting 9ths, 13ths, or 6ths to make things more interesting.

Also, listen to what other players do. Put on a blues record and pay attention to the chords. You’ll hear these substitutions everywhere once you know what to listen for.

Practice This

Start by learning the chord shapes. Don’t worry about the theory—just get the voicings under your fingers and hear how they sound.

Then, take a basic 12 bar blues and start substituting. Play through it with plain 7th chords first, then go back and replace some of them with 9ths or 13ths. Hear the difference.

You don’t have to substitute every chord. Sometimes just changing the last chord in a progression—the turnaround—is enough to make the whole thing sound more sophisticated.

Going Deeper with Ninth Chords

If you want to master ninth chords specifically, we’ve got focused lessons that break down the exact fingerings and techniques. Start with how to play the D9 chord—it covers the tricky finger positioning and that common fourth string problem most players struggle with.

For moveable shapes you can use anywhere on the neck, check out root 6 ninth chord voicings. And if you want that aggressive Hendrix sound, the sharp 9 chord lesson shows you how to add that distinctive edge to your blues playing.

What’s Next

This lesson is part 3 of a three-part series on blues chords. If you haven’t already, go back and check out part 1 on dominant 7th chords and part 2 on the I-IV-V progression.

Now that you’ve got the foundation of blues chords, the next step is to work these substitutions into your playing. Don’t force them—just try them out and see what sounds good. Over time, you’ll develop your own sense of when to use a plain chord and when to add some color.