The Open A7 Chord

The Formula of the Chord

The A7 chord is a versatile and commonly used chord in blues, rock, and jazz music. It has a bright and slightly edgy sound that adds tension and interest to chord progressions. The formula for a dominant 7th chord consists of four intervals: the root (R), the major third (3), the perfect fifth (5), and the minor seventh (b7). For the A7 chord, the specific notes involved are:

• Root (R): A
• Major Third (3): C#
• Perfect Fifth (5): E
• Minor Seventh (b7): G

In the open A7 chord, the voicing we play includes these notes distributed across the strings as follows:

• 5th string (A): A (R)
• 4th string (D): E (5)
• 3rd string (G): G (b7)
• 2nd string (B): C# (3)
• 1st string (E): Open E (5)

How to Play the Chord

To play the open A7 chord using the A, D, G, B, and E strings, follow these step-by-step instructions:

1. Open A String: Start by playing the 5th string (A string) open. This string produces the root note, A (R).
2. Middle Finger: Place your middle finger on the 2nd fret of the 4th string (D string). This will produce the note E (5).
3. Open G String: Leave the 3rd string (G string) open. This string produces the note G (b7).
4. Ring Finger: Place your ring finger on the 2nd fret of the 2nd string (B string). This will produce the note C# (3).
5. Open High E String: Leave the 1st string (high E string) open. This string produces the note E (5).

Ensure your fingers are pressing down firmly just behind the frets to get a clear sound. The 6th string (E string) is typically not played in this chord voicing, but if it rings out, it still contains a note (E) that is part of the chord structure.

Chord Visualisation

Below is the tablature to help you visualise the A7 chord:

Tablature:

e|---0---| (Open String)
B|---2---| (Ring Finger)
G|---0---| (Open String)
D|---2---| (Middle Finger)
A|---0---| (Open String)
E|---x---| (Do not play)

By following these instructions, you should be able to play the open A7 chord effectively. This chord shape is straightforward and adds a rich, bluesy flavour to your playing.