The ability to read a chord symbol and name the pitches of its chord is an essential skill for all musicians. I use it constantly in all of my music theory, analysis and orchestration courses to quickly describe musical harmony while dispensing of the need to suss out harmony from a written-out texture. It is, of course, also the foundation of jazz and pop improvisation.
Students of classical music often do not learn how to interpret these symbols beyond plain triads, so I am providing this lesson as an introduction for those students.
Chord symbols for triads follow these principles:
- A capital letter indicates the chord root.
- A capital letter all by itself indicates a major triad (C = C major, B♭ = B-flat major, and so forth). Major triads can also be indicated by a capital letter followed by a capital “M” (CM = C Major, B♭M = B-flat Major).
- A capital letter followed by a lower-case “m” indicates a minor triad (Cm = C minor; F♯m = F-sharp minor). Sometimes both letters are lower-case (cm, f♯m, etc.), and infrequently, the lower-case “m” is left off, using a lower-case chord-root to indicate a minor chord (c = C minor); this will not be used in this course. In some jazz charts, the “minus” symbol (-) indicates a minor triad (C- = C minor); this will also not be used in this course.
- A capital letter followed by a ° or + symbol indicates diminished and augmented triads, respectively (B° = B diminished, G+ = augmented). Sometimes, instead of the ° and + symbols, the abbreviations “dim” and “aug” will be found (Bdim or Gaug).
Seventh chords use these principles:
- A pitch name followed by “7” indicates a dominant seventh (major triad with minor seventh) chord, no matter its role in the key.
- A pitch name followed by M7 or Δ7 indicates a major seventh (major triad with major seventh) chord.
- A pitch name followed by m7 or min7 (or -7) indicates a minor seventh (minor triad with minor seventh) chord. By combining the “m” and “Δ” symbols, aminor/major chord (minor triad with major seventh) is indicated.
- A pitch name followed by ø7 or halfdim7 indicates a half-diminished seventh (diminished triad with minor seventh) chord (there is another way to show this that is explained below under “inverted chords”).
- A pitch name followed by °7 or dim7 indicates a fully-diminished seventh (diminished triad with diminished seventh) chord.
- Augmented triads can also have sevenths added. aug7 or (+7) chords are augmented triads with a minor seventh over the root, like a dom7 with raised fifth. augΔ7 indicates an augmented triads with a major seventh over the root.
“Sus” and “add” chords
All other chords described here are formed by stacking thirds: a root note, a third above that (the “third”), a third above that (the “fifth”), a third above that (the “seventh”), and so on. “Sus” and “add” chords are different. The sus4 chord is formed when the fourth above the root replaces the third; the sus2 chord is formed when the second above the root replaces the third. These chords are neither major nor minor — it’s as if the chord is frozen in a moment that a 4-3 suspension or 2-3 retardation is occurring (the suspension may or may not resolve). An add2 chord adds a note a second above the root to the triad.
The difference between sus or add chords and extended chords (see below) is that extended chords tend to have a seventh as a matter of course. Sus and add chords do not.
Sometimes a slash ( / ) followed by a pitch-name is added to the chord symbol, indicating its inversion. This has nothing to do with secondary dominant chords, which also use a slash (as in “V7/V”) for a very different purpose.
For chords in inversion, the symbol to the left of the slash indicates a whole chord and the pitch-name to the right of the slash indicates the chord’s lowest note. If there is no slash, the chord is assumed to be in root position.
- G7 = G dominant seventh chord in root position
- C/E = C major triad in first inversion (E is its lowest pitch).
- F♯m7/E = F♯ minor seventh chord in third inversion (E is its lowest pitch).
The pitch that follows the slash is almost always a member of the chord, but sometimes musicians play “fast and loose” with the use of this notation in pop and rock music. For instance, the symbol Fm/D might be used to indicate a Dø7 chord, or F/G might be used for a G9sus4 chord (see below for how to interpret “extended chords”).
“Extended chords” are harmonies that include chord members higher than sevenths; these are most common in jazz. Simply keep adding thirds above the notes of a seventh chord to find the chord’s ninth, eleventh, and thirteenth:
We call them “ninths,” “elevenths” and “thirteenths” regardless of the octave in which they are found. “Ninths” are like seconds (a 9th is one octave larger than a second), “elevenths” are like fourths (an 11th is one octave larger than a fourth) and “thirteenths” are like sixths (a 13th is one octave larger than a sixth).
- Not all chord members may be present in an extended chord; most often, some chord tones are omitted. To avoid having extremely thick chords of six or seven notes, it is common to leave out the fifth, the second-highest chord member, or even the root.
- The highest number is the only one used; in a D♭11 chord, it is assumed that there is a seventh or ninth, but no 13th.
- Flats and sharps can be added (usually in parenthesis) to numbers to show chord alterations. Without flats and sharps added to numbers it is assumed that chord extensions are major (9ths or 13ths) or perfect (11ths). Regardless of a chord’s position in the key, flats are added to numbers to lower that chord-member a half-step and sharps are added to raise it a half-step. Common alterations are:
- “flat-9” : D7(♭9) = D-F#-A-C-E♭
- “sharp-11” : D7(♯11) = D-F#-A-C-E-G♯
- “flat-13” : D7(♭13) = D-F#-A-C-E-G-B♭
- combinations, like : D7(♭9/♯11) = D-F#-A-C-E♭-G♯
- Extended chords are named like seventh chords, but the highest chord member is substituted for the number 7. For instance, a C9 chord is a dominant seventh chord with a major 9th added; its pitches are C-E-G-B♭-D. A Bm13 chord is a minor seventh chord with major 13th (an possibly major 9th and/or perfect 11th) added; its pitches are B-D-F♯-A-C♯-E-G♯ because B-D-F♯-A forms a minor 7th chord, C♯ is a major 9th above B, E is a perfect 11th above B, and G♯ is a major 13th above B.
- Jazz charts often have a strange symbol for half-diminished seventh chords: a minor seventh chord with flattened fifth, as in Fm7(♭5). It makes sense, sort of. Similarly, an augmented seventh chord can be written as a dominant seventh chord with ♯5.
Try it yourself
What are the pitches that make up each of these chords?
(1) F-A-C (2) G-B♭-D (3) D♭-F-A♭-C, “major seventh” (4) D-F♯-A♯ (5) F♯-A-C (6) A-C-E, E is bass (7) B♭-D-F-A♭ (8) C-E♭-G-B♭, E♭ is bass (9) C♯-E-G-B♭ (10) A-C-E♭-G “half-diminished 7th” (11) A♭-C-E♭-G♭-B♭ (12) E-G♯-B-D-F♯-A♯ (13) F-A-C-E-G-B♭-D♭ (14) E♭-G-B♭-D♭-F♭-A
Use a chord symbol to name each of these chords:
(1) Gm7(♭5)/E or Gø7/E (2) B♭Maj7 or B♭Δ7 (3) Adim7 or A°7 (4) D/F♯ (5)Dm(maj7) or DmΔ7 (6) Caug7 or C+7 (7) C7(♭9) (8) Cm9 – 5th is omitted (9)A7(♯11) – 5th & 9th are omitted (10) D7(♭9/♭13) – 5th & 11th are omitted
This Article first appeared on Professor Adam Silverman’s blog, Music Theory Prof Blog