In music

Music

Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...

 and musical analysis

Musical analysis

Musical analysis is the attempt to answer the question how does this music work?. The method employed to answer this question, and indeed exactly what is meant by the question, differs from analyst to analyst, and according to the purpose of the analysis. According to Ian Bent , analysis is "an...

, a subsidiary chord is an elaboration of a principal harmonic

Harmony

In music, harmony is the use of simultaneous pitches , or chords. The study of harmony involves chords and their construction and chord progressions and the principles of connection that govern them. Harmony is often said to refer to the "vertical" aspect of music, as distinguished from melodic...

 chord

Chord (music)

A chord in music is any harmonic set of two–three or more notes that is heard as if sounding simultaneously. These need not actually be played together: arpeggios and broken chords may for many practical and theoretical purposes be understood as chords...

 in a chord progression

Chord progression

A chord progression is a series of musical chords, or chord changes that "aims for a definite goal" of establishing a tonality founded on a key, root or tonic chord. In other words, the succession of root relationships...

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If the principal chord (X) is partially replaced by the subsidiary (Y), there are three possible positions - beginning, middle, and end - for the subsidiary:

X–Y

Y–X

X–Y–X

For example, a subsidiary chord in a modulation

Modulation (music)

In music, modulation is most commonly the act or process of changing from one key to another. This may or may not be accompanied by a change in key signature. Modulations articulate or create the structure or form of many pieces, as well as add interest...

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A subsidiary chord may be a chord with related function

Diatonic function

In tonal music theory, a diatonic function is the specific, recognized role of each of the 7 notes and their chords in relation to the diatonic key...

 and/or sharing pitches, for example in E major, Cm (C-E-G) as a subsidiary for E (E-G-B), which share two of three pitches and are related as tonic parallel

Tonic parallel

In music theory, the tonic parallel is a diatonic function and chord, relative to the tonic, and thus considered to have or fulfill the function of the tonic. The term is used in German theory and derives from the work of Hugo Riemann. It is abbreviated "Tp" in major and "tP" in minor.In C major:*...

 (vi) and tonic

Tonic (music)

In music, the tonic is the first scale degree of the diatonic scale and the tonal center or final resolution tone. The triad formed on the tonic note, the tonic chord, is thus the most significant chord...

(I).