The "A Dorian chord" most commonly refers to the A minor chord (Am) or A minor seven chord (Am7), which functions as the tonic chord of the A Dorian mode. While "Dorian" is a musical mode or scale rather than a chord type itself, when musicians refer to an "A Dorian chord," they are typically indicating the home or root chord that is built from and represents the A Dorian scale.
Understanding the A Dorian Mode
To understand the A Dorian chord, it's essential to first know the notes of the A Dorian mode. The A Dorian mode is a minor-type scale with a distinct quality due to its unique interval structure.
The notes of A Dorian are:
- A (Root)
- B (Major 2nd)
- C (Minor 3rd)
- D (Perfect 4th)
- E (Perfect 5th)
- F# (Major 6th)
- G (Minor 7th)
The crucial note that differentiates Dorian from a natural minor scale is the major 6th (F# in the key of A). A natural minor scale would have a minor 6th (F). This single sharped note gives Dorian its characteristic sound—often described as slightly brighter or more "open" than natural minor.
Building the A Dorian Chord (Tonic)
When we talk about the "A Dorian chord" in the singular, we're usually referring to the tonic chord (the chord built on the root note, A).
- Triad: The basic A Dorian triad is formed by stacking the root, minor third, and perfect fifth from the A Dorian scale: A - C - E. This forms an A minor (Am) chord.
- Seventh Chord: In most contemporary music, especially jazz and fusion, the A Dorian tonic is often played as a seventh chord. By adding the minor seventh (G) from the scale, we get A - C - E - G. This forms an A minor seven (Am7) chord. This Am7 chord is very common for establishing a Dorian sound.
- Extended Chords: For even richer harmonic textures, further extensions from the A Dorian scale can be added, such as the 9th (B) or 11th (D).
- Am9: A - C - E - G - B
- Am11: A - C - E - G - B - D
Chords that Define the Dorian Sound
While the Am or Am7 chord is the tonic, the Dorian sound is truly established when other chords from the mode are used, particularly those that highlight the major 6th (F# in A Dorian).
One of the most effective ways to emphasize the Dorian quality in a chord progression is by incorporating the major IV chord. In A Dorian, the IV chord is D major (D - F# - A). The presence of the F# within this D major chord strongly reinforces the Dorian mode, as this F# is the defining characteristic note. Using this D major chord in conjunction with the Am or Am7 chord helps to clearly establish the Dorian sound.
Here's a list of common diatonic chords found in the A Dorian mode:
| Chord Degree | Chord Type | Notes | Example in A Dorian |
|---|---|---|---|
| I | Minor 7th | Root, b3, 5, b7 | Am7 (A-C-E-G) |
| II | Minor 7th | Root, b3, 5, b7 | Bm7 (B-D-F#-A) |
| III | Major 7th | Root, 3, 5, 7 | Cmaj7 (C-E-G-B) |
| IV | Dominant 7th | Root, 3, 5, b7 | D7 (D-F#-A-C) |
| V | Minor 7th | Root, b3, 5, b7 | Em7 (E-G-B-D) |
| VI | Minor 7th (b5) | Root, b3, b5, b7 | F#m7b5 (F#-A-C-E) |
| VII | Major 7th | Root, 3, 5, 7 | Gmaj7 (G-B-D-F#) |
Note: While a D7 chord is listed as the IV chord in the table above, the reference specifically highlights the D major triad (D-F#-A) as containing the F# and thus strongly establishing the Dorian feel.
Practical Insights
- Jazz and Funk: The Dorian mode is widely used in jazz, funk, and R&B for improvisation and chord progressions. A common vamp might be switching between Am7 and D7, or Am7 and Gmaj7, effectively utilizing the sounds of the mode.
- Melodic Importance: When improvising over an Am7 chord in a Dorian context, emphasizing the F# will distinctly bring out the Dorian sound, differentiating it from a regular A natural minor or A Phrygian sound.
