Chord Symbols
Analytic practice in Jazz recognizes four basic chord types, plus diminished seventh chords. The four basic chord types are major seventh, minor seventh, half-diminished--which is also known as minor seventh flat five, and dominant. When written in a jazz chart, these chords may have alterations specified in parentheses after the chord symbol. An altered note is a note which is a deviation from the canonical chord tone.
There is variety in the chord symbols used in jazz notation. A jazz musician must have facility in the alternate notation styles which are used. The following chord symbol examples use C as a root tone for example purposes.
| Equivalent Symbols | Chord tones in example key | Name | Audio | ||
|---|---|---|---|---|---|
| C∆, CM7, CMaj7 | C E G B | major 7th chord | Play | ||
| C-7, Cm7, Cmin7 | C E♭ G B♭ | minor 7th chord | Play | ||
| C∅, Cm7♭5, C-7♭5 | C E♭ G♭ B♭ | half-diminished seventh chord | Play | ||
| C7 | C E G B♭ | dominant 7th chord | Play | ||
| Co7, Cdim7 | C E♭ G♭ B | fully diminished 7th chord | Play | ||
| Csus7 | C F G B♭ | dominant or minor suspended 4th chord | Play |
Most jazz chord symbols designate four notes. Each typically has a "role" as root, third, fifth, or seventh, although they may be severely altered and possibly use an enharmonic spelling which masks this underlying identity. For example, jazz harmony theoretician Jim Knapp has suggested that the ♭9 and even the ♯9 alterations are functioning in the root role.
The jazz chord naming system is as deterministic as the composer wishes it to be. A general rule of thumb is that chord alterations are included in a chart only when the alteration appears in the melody or is crucial to essence of the composition. Skilled improvisers are able to supply an idiomatic, highly altered harmonic vocabulary even when written chord symbols contain no alterations.
It is possible to specify chords with more than four notes. For this, the word add is included within the parentheses containing the alteration. For example the chord Cm(∆,add 2) contains the notes (C D E♭ G B).
Read more about this topic: Jazz Harmony
Famous quotes containing the words chord and/or symbols:
“Give me the keys. I feel for the common chord again,
Sliding by semi-tones till I sink to a minor,—yes,
And I blunt it into a ninth, and I stand on alien ground,
Surveying a while the heights I rolled from into the deep;
Which, hark, I have dared and done, for my resting-place is found,
The C Major of this life: so, now I will try to sleep.”
—Robert Browning (1812–1889)
“Eloquence must be grounded on the plainest narrative. Afterwards, it may warm itself until it exhales symbols of every kind and color, speaks only through the most poetic forms; but first and last, it must still be at bottom a biblical statement of fact.”
—Ralph Waldo Emerson (1803–1882)