Primary Triad on:
[Wikipedia]
[Google]
[Amazon]
In 
In C major these are:
*I C
*V G
*IV F
*vi Am
*iii Em
*ii Dm
*vii Bdim
In a minor key triads i and iv are 
Auxiliary chords may be considered parallel and contrast chords derived from the primary triads. For example, the supertonic, ii, is the subdominant parallel, relative of IV (in C: a d minor chord is the subdominant parallel, the subdominant is an F major chord). Being a parallel chord in a major key it is derived through raising the fifth a major second (C of F–A–C rises to D → F–A–D, an inversion of D–F–A). Alternatively, secondary triads may be considered ii, iii, and vi.Lancaster & Renfrow (2008). ''Alfred's Group Piano for Adults: Student Book 2'', p.77. . In C major these are:
*ii Dm
*iii Em
*vi Am
In A minor these are:
*ii Bdim
*III C
*VI F
In music
Music is generally defined as the The arts, art of arranging sound to create some combination of Musical form, form, harmony, melody, rhythm or otherwise Musical expression, expressive content. Exact definition of music, definitions of mu ...
, a primary triad is one of the three triads, or three-note chords
Chord may refer to:
* Chord (music), an aggregate of musical pitches sounded simultaneously
** Guitar chord a chord played on a guitar, which has a particular tuning
* Chord (geometry), a line segment joining two points on a curve
* Chord ...
built from major or minor third
In music theory, a minor third is a musical interval that encompasses three half steps, or semitones. Staff notation represents the minor third as encompassing three staff positions (see: interval number). The minor third is one of two com ...
s, most important in tonal and diatonic
Diatonic and chromatic are terms in music theory that are most often used to characterize scales, and are also applied to musical instruments, intervals, chords, notes, musical styles, and kinds of harmony. They are very often used as a p ...
music, as opposed to an auxiliary triad or secondary triad.
Each triad found in a diatonic key corresponds to a particular diatonic function
In music, function (also referred to as harmonic function) is a term used to denote the relationship of a chord"Function", unsigned article, ''Grove Music Online'', . or a scale degree to a tonal centre. Two main theories of tonal functions exist ...
. Functional harmony
In music, harmony is the process by which individual sounds are joined together or composed into whole units or compositions. Often, the term harmony refers to simultaneously occurring frequencies, pitches ( tones, notes), or chords. Howev ...
tends to rely heavily on the primary triads: triads built on the tonic, subdominant, and dominant degrees.Harrison, Daniel (1994). ''Harmonic Function in Chromatic Music: A Renewed Dualist Theory and an Account of its Precedents'', p.45. . Cited in Deborah Rifkin. "A Theory of Motives for Prokofiev's Music", p.274, ''Music Theory Spectrum'', Vol. 26, No. 2 (Autumn, 2004), pp. 265-289. University of California Press on behalf of the Society for Music Theory The roots of these triads begin on the first, fourth, and fifth degrees (respectively) of the diatonic scale, otherwise symbolized: I, IV, and V (again, respectively). Primary triads, "express function clearly and unambiguously." The other triads of the diatonic key include the supertonic
In music, the supertonic is the second degree () of a diatonic scale, one whole step above the tonic. In the movable do solfège system, the supertonic note is sung as ''re''.
The triad built on the supertonic note is called the supertonic cho ...
, mediant, sub-mediant, and leading-tone, whose roots begin on the second, third, sixth, and seventh degrees (respectively) of the diatonic scale, otherwise symbolized: ii, iii, vi, and viio (again, respectively). They function as auxiliary or supportive triads to the primary triads.
In C major these are:
*I C
*V G
*IV F
*vi Am
*iii Em
*ii Dm
*vii Bdim
In a minor key triads i and iv are minor chord
In music theory, a minor chord is a chord that has a root, a minor third, and a perfect fifth. When a chord comprises only these three notes, it is called a minor triad. For example, the minor triad built on C, called a C minor triad, has pitch ...
s, but in chord V the leading note is generally raised to form a major chord
In music theory, a major chord is a chord that has a root, a major third, and a perfect fifth. When a chord comprises only these three notes, it is called a major triad. For example, the major triad built on C, called a C major triad, has pitche ...
.Eric Taylor (2009). ''Music Theory in Practice Grade 4'', p.22. . ABRSM For example, in A minor the primary triads are Am, Dm and E. Chord v (minor) in a minor key may be considered a primary triad, but its use is rare in common practice harmony.
Auxiliary chords may be considered parallel and contrast chords derived from the primary triads. For example, the supertonic, ii, is the subdominant parallel, relative of IV (in C: a d minor chord is the subdominant parallel, the subdominant is an F major chord). Being a parallel chord in a major key it is derived through raising the fifth a major second (C of F–A–C rises to D → F–A–D, an inversion of D–F–A). Alternatively, secondary triads may be considered ii, iii, and vi.Lancaster & Renfrow (2008). ''Alfred's Group Piano for Adults: Student Book 2'', p.77. . In C major these are:
*ii Dm
*iii Em
*vi Am
In A minor these are:
*ii Bdim
*III C
*VI F
See also
* Subsidiary chordReferences
{{Chords Chords