Extensions
Chord extensions you can hear: 9ths, 11ths and 13ths
The minor ninth rule
A tension a minor ninth above a chord tone clashes hard enough to swallow the chord. That is an avoid note. Over Cmaj7, F sits a minor ninth above E, the third, so the natural eleven is avoided and the sharp eleven is not. On a dominant, a minor ninth above the root is an alteration rather than a fault, because the chord resolves through its third and seventh, which is why G7 can take a flat nine.
Every chord of C major, and what it can take
The available tensions below are the ones that clash with no chord tone and are notes of the key. Play each chord with two of its tensions added.
Cmaj7 Imaj7
Takes 9 13 · avoid 11
Plays Cmaj7(9 13)
Dm7 ii7
Takes 9 11 13
Plays Dm7(11 13)
Em7 iii7
Takes 11 · avoid
Plays Em7(11)
Fmaj7 IVmaj7
Takes
Plays
G7 V7
Takes 9 13 · avoid 11
Plays G7(9 13)
Am7 vi7
Takes 9 11 · avoid
Plays Am7(9 11)
viiø7
Takes · avoid
Plays
Alterations on the dominant
Outside the key, a dominant can take flat and sharp nines, a sharp eleven and a flat thirteen. Those notes come from the modes of melodic minor: Lydian dominant for the sharp eleven, the altered scale for all of them at once. See the modes.
Every chord on this page is spelled and voiced by Tonalia's music engine.