Guitar Chords A7: Magic of Dominant 7th Chords

Introduction

Dominant 7th chords are a cornerstone of many music styles, especially blues, jazz, and rock. Their unique sound brings a sense of tension and anticipation, making them a perfect tool for adding color and movement to your playing. In this article, we’ll explore the basics of dominant 7th chords, specifically focusing on the “guitar chords A7,” and discuss how to use them effectively, particularly in a blues context. We’ll also look at some iconic songs that utilize these chords to illustrate their versatility and power.

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Understanding Dominant 7th Chords

Before diving into specific applications, let’s define what a dominant 7th chord is. In music theory, a dominant 7th chord consists of a root note, a major third, a perfect fifth, and a minor seventh. This combination of notes gives the dominant 7th chord its characteristic sound—a blend of stability and tension.

For example, the A7 chord is constructed as follows:

• Root (A): The starting note, which gives the chord its name.
• Major Third (C#): Four half steps above the root, this note defines the chord as major.
• Perfect Fifth (E): Seven half steps above the root, providing harmonic stability.
• Minor Seventh (G): Ten half steps above the root, adding tension and making it a dominant 7th chord.

When played together, these notes create a rich, full sound that demands resolution, often to the tonic chord of the key. This tension and resolution is a fundamental aspect of Western music, creating a sense of movement and emotional expression.

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The Role of Dominant 7th Chords in Music

Dominant 7th chords play a crucial role in establishing the harmonic structure of a piece. They are most commonly found as the fifth chord in a key, known as the V7 chord, which leads back to the tonic (I) chord. This V7 to I movement is one of the most common chord progressions in music, creating a satisfying sense of resolution.

1. Blues and Dominant 7th Chords

Blues music is one of the genres where dominant 7th chords are used extensively. In a standard 12-bar blues progression, all three primary chords (I, IV, V) are typically dominant 7th chords. This use of dominant 7ths gives blues its distinctive sound—both soulful and slightly dissonant, filled with emotional depth.

For example, in the key of A, a typical 12-bar blues progression would use the following chords:

1. Four bars of A7 (I7)
2. Two bars of D7 (IV7)
3. Two bars of A7 (I7)
4. One bar of E7 (V7)
5. One bar of D7 (IV7)
6. One bar of A7 (I7)
7. One bar of E7 (V7)

This simple yet powerful progression forms the foundation of countless blues songs, from Muddy Waters’ “Hoochie Coochie Man” to B.B. King’s “The Thrill Is Gone.” The use of the A7 chord as the I chord creates a strong, assertive sound, setting the tone for the entire piece.

2. Rock and Dominant 7th Chords

Dominant 7th chords also appear frequently in rock music. Their slightly gritty sound adds edge and excitement, making them a favorite among guitarists looking to infuse their playing with energy and raw emotion. The Rolling Stones’ “Honky Tonk Women” uses dominant 7th chords extensively, showcasing their ability to drive a song forward and create a memorable hook.

In this song, the A7 chord is used as a main building block, delivering the bluesy, slightly rebellious feel that defines much of the Stones’ music. The tension within the A7 chord pushes the song forward, keeping the listener engaged.

3. Jazz and Dominant 7th Chords

In jazz, dominant 7th chords are often extended and altered to create even more complex sounds. Jazz musicians might add a ninth, eleventh, or thirteenth to a dominant 7th chord, or alter the fifth or ninth to create a variety of colorful harmonies. These chords are used to create tension and interest, leading the listener through a complex harmonic journey.

For instance, in a jazz context, the A7 chord might become an A9 or A13, adding even more layers to the harmonic texture. Songs like Miles Davis’ “All Blues” and John Coltrane’s “Giant Steps” utilize these extended dominant chords, showcasing their versatility and depth.

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How to Play Dominant 7th Chords on Guitar

Now that we’ve discussed the theory behind dominant 7th chords, let’s look at how to play them on the guitar. We’ll start with the A7 chord, one of the most common and useful dominant 7th chords.

Guitar Chords A7 Open Position

The A7 chord can be played in the open position, making it accessible even for beginners:

1. Place your first finger (index) on the 2nd fret of the 4th string (D).
2. Leave the 3rd string (G) open.
3. Place your second finger (middle) on the 2nd fret of the 2nd string (B).
4. Leave the 1st string (high E) open.
5. Strum all six strings.

This version of A7 is easy to play and has a bright, ringing sound that works well in many musical contexts.

A7 Barre Chord Shape

For a fuller sound, you can play the A7 as a barre chord:

1. Barre all the strings on the 5th fret with your first finger.
2. Place your third finger (ring) on the 7th fret of the 5th string (A).
3. Place your fourth finger (pinky) on the 7th fret of the 3rd string (G).

This version of the guitar chords A7 has a deeper, more resonant sound and is useful in blues and rock settings.

Guitar Chords A7 Movable Shape

The A7 shape is also movable up and down the neck, meaning you can play it in different keys by moving it to different frets. For example, sliding the entire shape up two frets transforms it into a B7 chord, up three frets into a C7 chord, and so on. This flexibility makes it a valuable shape to learn. Check out this blog post on Jazzguitarlicks.com.

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Incorporating Guitar Chords A7 into Your Playing

With the A7 chord under your fingers, you can start incorporating it into your playing. Here are some practical tips and ideas:

1. 12-Bar Blues in A

As mentioned earlier, guitar chords A7 is central to the 12-bar blues progression in the key of A. Try playing the A7 chord along with D7 and E7 to get a feel for the blues. Focus on the groove and feel, and experiment with different strumming patterns to bring out the bluesy character of the chords.

2. Mix A7 with Other Chords

The A7 chord can be used alongside other chords to create interesting progressions. Try playing a progression like A7 – D – E7 – A7. This progression is simple yet effective, and can serve as the basis for many songs. Notice how the dominant 7th chords (A7 and E7) add tension, while the major chord (D) provides resolution.

3. Use guitar chords A7 as a Transition Chord

Dominant 7th chords are great for transitions. You can use A7 to move from one section of a song to another, or to transition between different keys. For example, if you’re playing a song in the key of D, you could use A7 to pivot to the key of A. The tension in the A7 chord creates a sense of movement, making the key change feel natural.

4. Experiment with Riffs and Licks

A7 is also a great chord for developing riffs and licks. Since the minor seventh (G) is a key part of the chord, you can create licks that emphasize this note. Try sliding into the G note from the F# (the major sixth) to create a bluesy sound. Use hammer-ons and pull-offs to add expression, and play around with bending the notes to create a vocal-like quality.

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Iconic Songs Featuring Dominant 7th Chords

To further understand the power of dominant 7th chords, let’s look at a few iconic songs that feature these chords prominently:

1. “Sweet Home Chicago” by Robert Johnson

“Sweet Home Chicago,” a classic blues standard, uses dominant 7th chords extensively. The song follows a typical 12-bar blues progression, with the A7 chord setting the tone. The dominant 7th chords give the song its driving, rhythmic feel, making it a timeless favorite among blues musicians.

2. “Pride and Joy” by Stevie Ray Vaughan

Another great example is Stevie Ray Vaughan’s “Pride and Joy.” This song is built around the use of dominant 7th chords, with Vaughan’s powerful guitar playing showcasing the expressive potential of these chords. The A7 chord features prominently, adding grit and intensity to the song’s bluesy vibe.

3. “Crossroads” by Cream

“Crossroads,” famously covered by Cream, is a blues-rock classic that makes extensive use of dominant 7th chords. The A7 chord is a key part of the song’s driving rhythm, creating a sense of urgency and power. Eric Clapton’s blistering guitar solos over the A7 chord highlight the chord’s ability to support both rhythm and lead playing.

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Conclusion

Dominant 7th chords, like A7, are indispensable tools for any guitarist. They bring a unique blend of tension and resolution, making them ideal for blues, jazz, rock, and many other styles. Whether you’re strumming through a 12-bar blues progression, crafting a catchy rock riff, or exploring complex jazz harmonies, dominant 7th chords provide the harmonic richness and emotional depth that can elevate your playing.

As you continue your guitar journey, experiment with different ways to use dominant 7th chords. Practice incorporating them into your chord progressions, riffs, and solos. By mastering these chords, you’ll unlock new dimensions in your playing and deepen your understanding of music’s harmonic language. So pick up your guitar, play an A7 chord, and let the music flow!