chord symbol

A shorthand system for notating chords, chord symbols are commonly used in popular and jazz music as a guide for the performer to improvise the melody or accompaniment. This is an alternative to Roman Numeral notation indicating individual chords without regard to the chord progression. 

Each chord symbol has four basic components: chord root, chord quality, chord extension, and chord alteration.

 

The chord symbol begins with a letter to indicate the root note of the basic triad. It is the only required component of a chord symbol.In this example, the letter “C” would indicate that the chord is a triad based on the pitch “C”. 

 

Chord Quality :

The root is often followed by an indication of the quality of the chord (major, minor, diminished, or augmented). If there is no quality indicated, the chord is assumed to be major.
Major: For example, the chord symbol “C” would indicate a C major triad with the notes C, E and G. This can also be notated “Cmaj”, “Cma”, or “CM” (see table below).
Minor: The chord symbol “Cm” would indicate a C minor triad with the notes C, E flat  and G. This can also be notated “Cmin”, “Cmi”, or “C-“. Occasionally, this may also be seen as a lower case letter. For example, “c” would indicate a C minor triad.
Diminished: The chord symbol “Cdim” would indicate a C diminished triad with the notes C, E flat and G. This can also be notated “Cº”.

Augmented: The chord symbol “Caug” would indicate a C augmented triad with the notes C, E and G sharp. This can also be notated “C+”.

The next component of the chord symbol is the extension, or a  number that indicates pitches that are added to the basic triad. The number represents the interval between the root and the highest additional note in the chord. The most common extension is the interval of a seventh. So “CM7” would indicate that the triad C – E – G would also include the seventh note above the root C or B flat.

Other common extensions include:

Sixth: A “C6” chord would indicate that the note a sixth above the root (A) should be added creating the chord C – E – G – A.

Ninth: A “C9” chord would include the ninth note  (D) above the root.  As an aside, this chord would typically include the seventh (B flat) as well making the chord  C  – E  – G  – B flat  - D.

Eleventh: A "C11" chord would include the eleventh note above the root (F ) along with the seventh , and ninth  notes  (C  – E  – G  – B flat  – D  – F ). Note: it is common to omit the third  (E ) of the chord .

Thirteenth: A "Cl3" chord would include the thirteenth (A ) along with the seventh , ninth  and eleventh  notes  (C  – E  – G  – B flat  – D  – F  - A ).

Chord Alterations: 

Any of  the added notes may be sharpened, indicated by a sharp sign  or plus "+" sign, or flattened, indicated by a flat sign or minus "-" sign . alterations would typically be shown as a superscript, or slightly higher than the other components of the chord symbol. For example, "Cmaj13^♯11" would indicate the chord C - E - G  - B flat - D  - F sharp, where the eleventh note F sharp has been raised one half step (one semitone. 

Another common alteration is the abbreviation 'sus ’ indicating a suspension . For example, "C sus " would indicate the third of a C triad would be raised to create a C - F - G triad where the F would resolve to the third (E) in the following chord.