The Four Qualities

Jazz looks like it has hundreds of chords. It has four, plus decoration.

Take any major scale and build a four-note chord on each degree, and you get only four qualities: major seventh, minor seventh, dominant seventh, and half-diminished. In the key of C that is Cmaj7, Dm7, Em7, Fmaj7, G7, Am7 and Bm7b5 — seven chords, four qualities, because the minor sevenths repeat.

So the first job is not learning chords. It is hearing which of four things a chord is.

Major seventh sounds settled and slightly dreamy. Minor seventh sounds dark but relaxed, not sad. Dominant seventh sounds unfinished — it wants to move somewhere. Half-diminished sounds tense and unstable, and it almost always appears just before a minor chord.

Learn one compact voicing of each, four or five strings, in the middle of the neck. Big open six-string shapes are the wrong tool here: in jazz the bass player has the low notes, and your job is the middle. Every chart below is movable, so none of them is stuck in one key.

Cmaj7

Cmaj7 — the settled one. The chord a tune ends on.

Dm7

Dm7 — dark and relaxed. You will play more of these than anything else.

G7

G7 — the restless one. It is pulling towards Cmaj7 and you can hear it.

Bm7♭5

Bm7♭5, the half-diminished. Tense, and nearly always a signpost to a minor chord.

Now use them. This track is in A minor and its changes cycle through all four qualities — A7, Dm7, Fmaj7, Em7, Am7 and Bm7 all appear.

Don't try to play along yet. Watch the chord changes as the track runs and say the quality out loud as each one arrives: major seven, minor seven, dominant, minor seven. Do that for two full minutes before you touch the guitar.

Recognising the quality before you play is the skill that makes the rest of this path work.

A minor fusion at 90 BPM. Call the quality of each chord out loud as it arrives.