Chord Symbols

A chord symbol is an expectation of tonality.
It is not a descriptor of what voicing should be played.
In fact, it is a better descriptor as what notes not to play.

For instance the chord symbol C,
does not necessarily mean you have to voice the major 7th in the chord.
It means if you are going to voice the 7th, make sure it's the major 7th!

The player has the freedom to voice the chord however they see fit.
Sometimes chords can even be substituted with entirely different chords,
as long as the tonality and/or function is fulfilled.

If an arrangement needs to express specific voicings,
sheet music, tablature, or chord diagrams should be used.

Do not write chords like D7sus4(add9, no5). That's nonsense.
D7(sus), D9(sus), or even C/D are much better options.
If a voicing needs to be specific, use a chord diagram such as: x5555x
else let the player voice the chord however they wish.

Anatomy of a chord symbol

Root Tonality (Tension) /Bass note
R T (T) /B
A 7 (9) /C
A7( 9)/C

Common tonalities for chord symbols:

6, 6/9, , 7, 9, 13,
7, 9, 13,
-, -7, -9, -11, -13,
-6, -6/9, 7,

7, 9,

, 7

Common available tensions for chord symbols:

5, 5, 9, 9, 11, 13, SUS, ALT, 7

Enharmonic and octave equivalents:

2 : 9
2 : 9
2 : 9 : 3

4 : 11
4 : 11 : 5

6 : 13
6 : 13 : 5

7 : 6

If chord of the same family and/or functions are interchangeable,
   why are there so many different symbols?

Because people over analyze voicings in their chord symbols!

Here are a few reasons why a transcriber or
   arranger might use a certain chord symbol:

• They transcribed so and so musician who played x/y chord voicing.
   (this is not a good use of chord symbols!)

• To make the player aware of a melody note,
   so the player can be careful not to play a voicing that would clash.
   (this is a good use of chord symbols)

• The arrangement calls for a specific voicing to be played.
   (Not great, use sheet music, tabs, or diagrams)