music Music is generally defined as the art of arranging sound to create some combination of form, harmony, melody, rhythm or otherwise expressive content. Exact definitions of music vary considerably around the world, though it is an aspe ...

, a closely related key (or close key) is one sharing many common tones with an original key, as opposed to a distantly related key (or distant key). In music

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. Howeve ...

, there are six of them: five share all, or all except one, pitches with a key with which it is being compared, and is adjacent to it on the

circle of fifths In music theory, the circle of fifths is a way of organizing the 12 chromatic pitches as a sequence of perfect fifths. (This is strictly true in the standard 12-tone equal temperament system — using a different system requires one interval of ...

and its relative major or minor, and one shares the same tonic. Such keys are the most commonly used destinations or transpositions in a

modulation In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the '' carrier signal'', with a separate signal called the ''modulation signal'' that typically contains informat ...

,Schonbrun, Marc (2006). ''The Everything Music Theory Book'', p.76. . because of their strong structural links with the home key. Distant keys may be reached sequentially through closely related keys by chain modulation, for example, C to G to D. For example, "One principle that every composer of

Haydn Franz Joseph Haydn ( , ; 31 March 173231 May 1809) was an Austrian composer of the Classical period. He was instrumental in the development of chamber music such as the string quartet and piano trio. His contributions to musical form have led ...

's day

Classical music era The Classical period was an era of classical music between roughly 1750 and 1820. The Classical period falls between the Baroque and the Romantic periods. Classical music has a lighter, clearer texture than Baroque music, but a more sophistic ...

] kept in mind was over-all unity of tonality. No piece dared wander too far from its tonic (music), tonic key, and no piece in a four-movement form dared to present a tonality not closely related to the key of the whole series." For example, the first movement of Mozart's Piano Sonata No. 7, K. 309, modulates only to closely related keys (the dominant, supertonic, and submediant).Benward & Saker (2009). ''Music in Theory and Practice: Volume II'', p.155. Eighth Edition. . Given a

major key In music theory, the key of a piece is the group of pitches, or scale, that forms the basis of a musical composition in classical, Western art, and Western pop music. The group features a '' tonic note'' and its corresponding '' chords'', ...

tonic (I), the related keys are: * ii (

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 ch ...

, the relative minor of the subdominant) *iii (

mediant In music, the mediant (''Latin'': to be in the middle) is the third scale degree () of a diatonic scale, being the note halfway between the tonic and the dominant.Benward & Saker (2003), p.32. In the movable do solfège system, the mediant note ...

, the relative minor of the dominant) *IV (

subdominant In music, the subdominant is the fourth tonal degree () of the diatonic scale. It is so called because it is the same distance ''below'' the tonic as the dominant is ''above'' the tonicin other words, the tonic is the dominant of the subdomina ...

Jones (1994), p.35-36.): one less

sharp Sharp or SHARP may refer to: Acronyms * SHARP (helmet ratings) (Safety Helmet Assessment and Rating Programme), a British motorcycle helmet safety rating scheme * Self Help Addiction Recovery Program, a charitable organisation founded in 199 ...

(or one more flat) around circle of fifths *V ( dominant): one more sharp (or one fewer flat) around circle of fifths *vi (

submediant In music, the submediant is the sixth degree () of a diatonic scale. The submediant ("lower mediant") is named thus because it is halfway between tonic and subdominant ("lower dominant") or because its position below the tonic is symmetrical to ...

or relative minorBarry, Barbara R. (2000). ''The Philosopher's Stone: Essays in the Transformation of Musical Structure'', p.19. .Benward & Saker (2003). ''Music: In Theory and Practice, Vol. I'', p.243. 7th edition. McGraw-Hill. . "Most modulations occur between ''closely related keys'', which are those keys that differ by no more than one accidental in the key signature."): different tonic, same key signature *i ( parallel minor): same tonic, different key signature Closely keys in C major

Specifically: : Starting from a minor key (i), the closely related keys are the mediant or relative major (III), the subdominant (iv), the minor dominant (v), the submediant (VI), the

subtonic In music, the subtonic is the degree of a musical scale which is a whole step below the tonic note. In a major key, it is a lowered, or flattened, seventh scale degree (). It appears as the seventh scale degree in the natural minor and descendin ...

(VII), and the parallel major (I). In the key of

A minor A minor is a minor scale based on A, with the pitches A, B, C, D, E, F, and G. Its key signature has no flats and no sharps. Its relative major is C major and its parallel major is A major. The A natural minor scale is: : Changes ...

, when we translate them to keys, we get: *

C major C major (or the key of C) is a major scale based on C, consisting of the pitches C, D, E, F, G, A, and B. C major is one of the most common keys used in music. Its key signature has no flats or sharps. Its relative minor is A minor and ...

D minor D minor is a minor scale based on D, consisting of the pitches D, E, F, G, A, B, and C. Its key signature has one flat. Its relative major is F major and its parallel major is D major. The D natural minor scale is: Changes needed ...

E minor E minor is a minor scale based on E, consisting of the pitches E, F, G, A, B, C, and D. Its key signature has one sharp. Its relative major is G major and its parallel major is E major. The E natural minor scale is: : Changes needed ...

F major F major (or the key of F) is a major scale based on F, with the pitches F, G, A, B, C, D, and E. Its key signature has one flat. Its relative minor is D minor and its parallel minor is F minor. The F major scale is: : F major is ...

G major G major (or the key of G) is a major scale based on G, with the pitches G, A, B, C, D, E, and F. Its key signature has one sharp. Its relative minor is E minor and its parallel minor is G minor. The G major scale is: Notable com ...

A major A major (or the key of A) is a major scale based on A, with the pitches A, B, C, D, E, F, and G. Its key signature has three sharps. Its relative minor is F-sharp minor and its parallel minor is A minor. The key of A major is the only k ...

Another view of closely related keys is that there are six closely related keys, based on the tonic and the remaining triads of the

diatonic scale In music theory, a diatonic scale is any heptatonic scale that includes five whole steps (whole tones) and two half steps (semitones) in each octave, in which the two half steps are separated from each other by either two or three whole st ...

, excluding the dissonant diminished triads. Four of the five differ by one accidental, one has the same key signature, and one uses the parallel modal form. In the key of

, these would be:

, and

C minor C minor is a minor scale based on C, consisting of the pitches C, D, E, F, G, A, and B. Its key signature consists of three flats. Its relative major is E major and its parallel major is C major. The C natural minor scale is: : Cha ...

. Despite being three sharps or flats away from the original key in the circle of fifths, parallel keys are also considered as closely related keys as the tonal center is the same, and this makes this key have an affinity with the original key. In modern music, the closeness of a relation between any two keys or sets of pitches may be determined by the number of tones they share in common, which allows one to consider modulations not occurring in standard major-minor tonality. For example, in music based on the

pentatonic scale A pentatonic scale is a musical scale with five notes per octave, in contrast to the heptatonic scale, which has seven notes per octave (such as the major scale and minor scale). Pentatonic scales were developed independently by many an ...

containing pitches C, D, E, G, and A, modulating a fifth higher gives the collection of pitches G, A, B, D, and E, having four of five tones in common. However, modulating up a

tritone In music theory, the tritone is defined as a musical interval composed of three adjacent whole tones (six semitones). For instance, the interval from F up to the B above it (in short, F–B) is a tritone as it can be decomposed into the three adj ...

would produce F, G, A, C, D, which shares no common tones with the original scale. Thus the scale a fifth higher is very closely related, while the scale a tritone higher is not. Other modulations may be placed in order from closest to most distant depending upon the number of common tones. Another view in modern music, notably in Bartók, a common tonic produces closely related keys, the other scales being the six other modes. This usage can be found in several of the Mikrokosmos piano pieces. When modulation causes the new key to traverse the bottom of the circle of fifths this may give rise to a

theoretical key In music theory, a theoretical key is a key whose key signature would have at least one double-flat () or double-sharp (). Double-flats and double-sharps are often used as accidentals, but placing them in the key signature (in music that uses e ...

, containing eight (or more) sharps or flats in its notated key signature; in such a case, notational conventions require recasting the new section in its enharmonically equivalent key.

Andranik Tangian Andranik Semovich Tangian (Melik-Tangyan) (Russian: Андраник Семович Тангян (Мелик-Тангян)); born March 29, 1952) is a Soviet Armenian-German mathematician, political economist and music theorist. Tangian is known ...

suggests 3D and 2D visualizations of key/chord proximity for both all major and all minor keys/chords by locating them along a single subdominant-dominant axis, which wraps a torus that is then unfolded.

See also

References

Further reading