In this lesson we learn how to form an A7 chord on piano. This chord is formed by combining the root, major third, perfect fifth and flat seventh of the A major scale. The notes of the A major scale are A – B – C# – D – E – F# – G# – A. So using the 7 chord formula 1 – 3 – 5 – b7, the notes of the chord, A7 are A – C# – E – G. Instead of playing the 7th note of the scale you play a semitone lower. So you don’t play G# but play G instead. In root position A is played with the first finger. C# is played with the second finger, E is played with the third finger and G is played with the fifth finger. A is the lowest note of the chord.
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We can play the A7 chord in other voicings or inversions. Study the diagram above. In its first inversion we move the note A an octave higher and the notes are in the following sequence: C# – E – G – A. In the second inversion, move c# an octave higher and the notes are now in the sequence E – G – A – C#. Finally, in the third inversion of A7, move E an octave higher and the pitches are now in the sequence G – A – C# – E. In every voicing or inversion the notes remain the same but the sequence changes. Learn how to play piano chords with the Piano For All piano course. 
A7 has other names and these are A dominant 7 and A dom7. However the most common way to write this chord is A7.
The A7 chord is really a combination of a major interval and two minor ones. Between A and C# we have a major interval. A major interval consists of two whole notes. Between C# and E we have a minor interval. A minor interval consists of one and a half notes (3 semitones). The other minor interval is between E and G.
When you play a dominant seventh chord, the chord “begs” you to play the perfect fourth above it. So in the case of A7, the next chord one would play afterwards is the chord, D, a perfect fourth above A.
To learn how to play other dominant seventh chords visit the main piano chords page. Return from A7 Chord to main Piano Chords page. You can also learn how to build other kinds of chords in all twelve keys.
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