Dominant 9th chords are commonly used in musical genres such as blues, funk and jazz.
In blues music, these chords appeared during the Chicago blues era. They created a more harmonically sophisticated sound evolving from the acoustic delta blues where dominant 7th chords were predominantly used.
The Dominant 9th Chord Notes
Dominant 9th chords are made of the notes 1,3,5,7b,9. There are built by adding the minor 7th and a major 9th to the major chord.
There are 3 types of 9th chords but when referring to a 9th chord (example: C9) it implies its dominant. The two other types of ninth chords are major and minor (identified as maj9 and min9).
Dominant 9th Chords Guitar Patterns
There are many ways to play dominant 9th chords on the guitar. I recommend starting with the most common and popular patterns.
Here is the most found pattern in Chicago blues guitar. It’s a great place to start.
More Dominant 9th Chords Guitar Patterns
Here are more interesting voicings you might want to learn and experiment with.
Dominant 9th Chords Inversions
Here are two other popular patterns. These are inversions since the root note is on the high E string. I find they sound different from above pattern and are very useful in blues and funk.
Dominant 9th Chords in Blues Progressions
You will find that these chords fit perfectly in a classic twelve bar blues progression.
Recommended Listening
These chords are found everywhere in blues. I would recommend you to take a listen to Are You Losing Your Mind from Buddy Guy or Scuttle Buttin’ from Stevie Ray Vaughan.