A9 guitar chords
A - C# - E - G - B
|A ninth chords are generally written as A9|
|A Major Scale||A - B - C# - D - E - F# - G#|
|Chord Formula||1 - 3 - 5 - ♭7 - 9|
|Notes||A - C# - E - G - B|
e |-3-| B |-2-| G |-4-| D |-2-| A |-0-| E |---|
e |-5-| B |-5-| G |-4-| D |-5-| A |-0-| E |---|
e |-7-| B |-5-| G |-6-| D |-5-| A |-0-| E |---|
- This chord is a dominant 9th chord which is a dominant 7th chord with an added 9th. It is an extended chord which includes the dominant 7th in its structure.
- If a chord with a symbol 9 is not preceded by the words major or maj, i.e., A9 as opposed to Amaj9, the 7th is always a dominant 7th (♭7).
- A 9th chord implies the presence of the preceding 1st, 3rd, 5th, ♭7th, before the added 9th.
- In the 2nd position chord, the 3rd is omitted... this is a particular voicing of the 9th chord where the third is omitted, and the 9th is played an octave lower... this could also be classed as a 7th suspended 2nd chord, in this case A7sus2. The chord formula is 1-2-5-♭7 = A-B-E-G (notes in the second position).
- A ninth chords: used mainly in jazz and alternate styles of music.
- Standard keys using the A ninth chord: D major/B minor.
Bm is the relative minor of D major which means both scales share the same notes. A9 (A - C# - E - G - B) utilizes notes belonging to the D Major & Bm Scale... D-E-F#-G-A-B-C#.