Guitar chord

Ry Cooder plays slide guitar, using an open tuning that allows major chords to be strummed by barring the strings at one fret.

In music, a guitar chord is a chord, or collection of notes usually sounded together at once, played on a guitar. The notes of the chord form an arpeggio when played sequentially rather than simultaneously. Chord voicings designed for the guitar can be optimized for many different purposes and playing styles.

Guitars can vary both in the number of strings and their tuning. Most guitars used in popular music have six strings and are tuned (from the lowest pitched string to the highest): E-A-D-G-B-E' (standard tuning). The intervals present among adjacent strings in this tuning can be written (in semitones) 5-5-5-4-5 (with perfect fourth intervals except for one major third interval between the G and the B). Conventionally, the string with the highest pitch (the thinnest) is called the first string, and the string having the lowest pitch is called the sixth. Standard tuning requires four chord-shapes for the major chords. There are separate chord-forms for chords having their root note on the third, fourth, fifth, and sixth strings. For a six-string guitar in standard tuning, it may be necessary to drop or omit one or more tones from the chord; this is typically the root or fifth. The layout of notes on the fretboard in standard tuning often forces guitarists to permute the tonal order of notes in a chord.

Guitar chords are dramatically simplified by the class of alternative tunings called regular tunings, in which the musical intervals are the same for each pair of consecutive strings. Regular tunings include major-thirds tuning, all-fourths, augmented-fourths, and all-fifths tunings. For each regular tuning, chord patterns may be diagonally shifted down the fretboard, a property that simplifies beginners' learning of chords and that simplifies advanced players' improvisation. On the other hand, in regular tunings, some conventional guitar chords may be more difficult to play.

Conventionally, guitarists double notes in a chord to increase its volume, an important technique for players without amplification; doubling notes and changing the order of notes also changes the timbre of chords. It can make a possible a "chord" which is composed of the all same note on different strings. Many chords can be played with the same notes in more than one place on the fretboard.

Musical fundamentals

The theory of guitar-chords respects harmonic conventions of Western music. Discussions of basic guitar-chords rely on fundamental concepts in music theory: the twelve notes of the octave, musical intervals, chords, and chord progressions.

Intervals

The chromatic circle lists the twelve notes of the octave. Consecutive notes differ by exactly one semitone.

A one-octave C major scale.

Initial eight harmonics on C, namely (C,C,G,C,E,G,B♭,C)  Play simultaneously 

Main article: Interval (music)

See also: Major scale

The octave consists of twelve notes. Its natural notes constitute the C major scale, (C, D, E, F, G, A, B, and C).

The intervals between the notes of a chromatic scale are listed in a table, in which the emboldened intervals are discussed in this article. The unison and octave intervals have perfect consonance. The perfect fifth interval is highly consonant, which means that the successive playing of the two notes from the perfect fifth sounds harmonious.

A semitone is the distance between two adjacent notes on the chromatic circle, which displays the twelve notes of an octave.

Intervals

Number of semitones	Minor, major, or perfect intervals	Audio	Harmoniousness
0	Perfect unison	Play	Open consonance
1	Minor second	Play	Sharp dissonance
2	Major second	Play	Mild dissonance
3	Minor third	Play	Soft consonance
4	Major third	Play	Soft consonance
5	Perfect fourth	Play	Ambivalence
6	Augmented fourth	Play	Ambiguous
7	Perfect fifth	Play	Open consonance
8	Minor sixth	Play	Soft consonance
9	Major sixth	Play	Soft consonance
10	Minor seventh	Play	Mild dissonance
11	Major seventh	Play	Sharp dissonance
12	Octave	Play	Open consonance

As indicated by their having been emboldened in the table, a handful of intervals—thirds (minor and major), perfect fifths, and minor sevenths—are used in the following discussion of fundamental guitar-chords.

As already stated, the perfect-fifths (P5) interval is the most harmonious, after the unison and octave intervals. An explanation of human perception of harmony relates the mechanics of a vibrating string to the musical acoustics of sound waves using the harmonic analysis of Fourier series. When a string is struck with a finger or pick (plectrum), it vibrates according to its harmonic series. When an open-note C-string is struck, its harmonic series begins with the terms (C,C,G,C,E,G,B♭,C). The root note is associated with a sequence of intervals, beginning with the unison interval (C,C), the octave interval (C,C), the perfect fifth (C,G), the perfect fourth (G,C), and the major third (C,E). In particular, this sequence of intervals contains the thirds of the C-major chord {(C,E),(E,G)}.

"With a note of music, one strikes the fundamental, and, in addition to the root note, other notes are generated: these are the harmonic series.... As one fundamental note contains within it other notes in the octave, two fundamentals produce a remarkable array of harmonics, and the number of possible combinations between all the notes increases phenomenally. With a triad, affairs stand a good chance of getting severely out of hand."

—Robert Fripp, Denyer (1992, p. 114)

Perfect fifths

The perfect-fifth interval is featured in guitar playing and in sequences of chords. The sequence of perfect fifths built on the C-major scale is used in the construction of major and minor triads.

The diminished fifth (b,f) replaces the second-to-the-last perfect fifth (b,f♯), for use in the construction of minor and major chords from the major scale on C (below).

Cycle of fifths

Concatenating the perfect fifths ((F,C), (C,G), (G,D), (D,A), (A,E), (E,B),...) yields the sequence of fifths (F,C,G,D,A,E,B,...); this sequence of fifths displays all the notes of the octave. This sequence of fifths shall be used in the discussions of chord progressions, below.

Power chord

The Who's Peter Townshend often used a theatrical "windmill" strum to play "power chords"—a root, fifth, and octave.

Main article: Power chord

The perfect-fifth interval is called a power chord by guitarists, who play them especially in blues and rock music. The Who's guitarist, Peter Townshend, performed power chords with a theatrical windmill-strum. Power chords are often played with the notes repeated in higher octaves.

Although established, the term "power chord" is inconsistent with the usual definition of a chord in musical theory, which requires that any chord have three (or more) distinct notes.

Chords in music theory

A brief overview

C Major (C,E,G) begins with the major third (C,E).

C Minor (C,E♭,G) begins with minor third (C,E♭).

Major and minor triads contain major-third and minor-third intervals in different orders.

The musical theory of chords is reviewed, to provide terminology for a discussion of guitar chords. Three kinds of chords, which are emphasized in introductions to guitar-playing, are discussed. These basic chords arise in chord-triples that are conventional in Western music, triples that are called three-chord progressions. After each type of chord is introduced, its role in three-chord progressions is noted.

Intermediate discussions of chords derive both chords and their progressions simultaneously from the harmonization of scales. The basic guitar-chords can be constructed by "stacking thirds", that is, by concatenating two or three third-intervals, where all of the lowest notes come from the scale.

Triads

Major

Both major and minor chords are examples of musical triads, which contain three distinct notes in the following order:

• the root;
• the third, which is above the root by either a major third or a minor third;
• the fifth, which is a perfect fifth above the root; consequently, the fifth is a third above the third—either a minor third above a major third or a major third above a minor third. The major triad has a root, a major third, and a fifth. (The major chord's major-third interval is replaced by a minor-third interval in the minor chord, which shall be discussed in the next subsection.)

Major chords

Chord	Root	Major third	Fifth
C	C	E	G
D	D	F♯	A
E	E	G♯	B
F	F	A	C
G	G	B	D
A	A	C♯	E
B	B	D♯	F♯

For example, the C major chord consists of the (root, third, fifth)-notes (C, E, G).

In popular music, a subset of triads are emphasized, the ones from the notes of the three major-keys (C, G, D), which also contain the notes of their relative minor keys (Am, Em, Bm).

Progressions

Stacking the C-major scale with thirds creates a chord progression  Play , traditionally enumerated with the Roman numerals I, ii, iii, IV, V, vi, vii^o. Its major-key sub-progression C-F-G (I-IV-V) is conventional in popular music. In this progression, the minor triads ii-iii-vi appear in the relative minor key (Am)'s corresponding chord progression.

Elvis Presley's "Hound Dog" used the I-IV-V chord progression.

The major chords are highlighted by the three-chord theory of chord progressions, which describes the three-chord song that is archetypal in popular music. When played sequentially (in any order), the chords from a three-chord progression sound harmonious ("good together").

The most basic three-chord progressions of Western harmony have only major chords. In each key, three chords are designated with the Roman numerals (of musical notation): The tonic (I), the subdominant (IV), and the dominant (V). While the chords of each three-chord progression are numbered (I, IV, and V), they appear in other orders.

Basic three-chord progressions

Key	Tonic (I)	Subdominant (IV)	Dominant (V)
C	C	F	G
D	D	G	A
E	E	A	B
G	G	C	D
A	A	D	E

In the 1950s the I-IV-V chord progression was used in "Hound Dog" (Elvis Presley) and in "Chantilly Lace" (The Big Bopper).

Major-chord progressions are constructed in the harmonization of major scales in triads. For example, stacking the C-major scale with thirds creates a chord progression, which is traditionally enumerated with the Roman numerals I, ii, iii, IV, V, vi, vii^o; its sub-progression C-F-G (I-IV-V) is used in popular music, as already discussed. Further chords are constructed by stacking additional thirds. Stacking the dominant major-triad with a minor third creates the dominant seventh chord, which shall be discussed after minor chords.

Minor

An A-minor scale has the same pitches as the C major scale, because the C major and A minor keys are relative major and minor keys.  Play 

A minor chord has the root and the fifth of the corresponding major chord, but its first interval is a minor third rather than a major third:

Minor chords

Chord	Root	Minor third	Perfect fifth
Cm	C	E♭	G
Dm	D	F	A
Em	E	G	B
Fm	F	A♭	C
Gm	G	B♭	D
Am	A	C	E
Bm	B	D	F♯

Minor chords arise in the harmonization of the major scale in thirds, which was already discussed: The minor chords have the degree positions ii, iii, and vi.

Minor three-chord progressions

Key	Tonic (I)	Subdominant (IV)	Dominant (V)
Cm	Cm	Fm	G7
Dm	Dm	Gm	A7
Em	Em	Am	B7
Gm	Gm	Cm	D7
Am	Am	Dm	E7

Major and minor keys that share the same key signature are paired as relative-minor and relative-major keys.

Minor chords arise as the tonic notes of minor keys that share the same key signature with major keys. From the major key's I-ii-iii-IV-V-vi-vii^o progression, the "secondary" (minor) triads ii-iii-vi appear in the relative minor key's corresponding chord progression as i-iv-v (or i-iv-V or i-iv-V7): For example, from C's vi-ii-iii progression Am-Dm-Em, the chord Em is often played as E or E7 in a minor chord progression. Among basic chords, the minor chords (D,E,A) are the tonic chords of the relative minors of the three major-keys (F,G,C):

Key signature	Major key	Minor key
B♭	F major	D minor
	C major	A minor
F♯	G major	E minor

The technique of changing among relative keys (pairs of relative majors and relative minors) is a form of modulation. Minor chords are constructed by the harmonization of minor scales in triads.

Seventh chords: Major-minor chords with dominant function

The previously noted chord progression with a dominant seventh  Play . The dominant seventh (V7) chord G7=(G,B,D,F) increases the tension with the tonic (I) chord C.

Adding a minor seventh to a major triad creates a dominant seventh (denoted V7). In music theory, the "dominant seventh" described here is called a major-minor seventh, emphasizing the chord's construction rather than its usual function. Dominant sevenths are often the dominant chords in three-chord progressions, in which they increase the tension with the tonic "already inherent in the dominant triad".

Dominant seventh chords

Chord	Root	Major third	Perfect fifth	Minor seventh
C7	C	E	G	B♭
D7	D	F♯	A	C
E7	E	G♯	B	D
F7	F	A	C	E♭
G7	G	B	D	F
A7	A	C♯	E	G
B7	B	D♯	F♯	A

The dominant seventh discussed is the most commonly played seventh chord.

Paul McCartney used an A-major I-IV-V7 chord-progression in "3 Legs", which is also an example of the twelve-bar blues.

Three-chord progressions

Key	Tonic (I)	Subdominant (IV)	Dominant (V)
C	C	F	G7
D	D	G	A7
E	E	A	B7
G	G	C	D7
A	A	D	E7

An A-major I-IV-V7 chord progression A-D-E7 was used by Paul McCartney in the song "3 Legs" on his album Ram.

These progressions with seventh chords arise in the harmonization of major scales in seventh chords.

Twelve-bar blues

Be they in major key or minor key, such I-IV-V chord-progressions are extended over twelve bars in popular music—especially in jazz, blues, and rock music. For example, a twelve-bar blues progression of chords in the key of E has three sets of four bars:

E-E-E-E7

A-A-E-E

B7-A-E-B7;

this progression is simplified by playing the sevenths as major chords. The twelve-bar blues structure is used by McCartney's "3 Legs", which was noted earlier.

Playing chords: Open strings, inversion, and note doubling

See also: Open string, Inversion (music), and Voicing (music)

The implementation of musical chords on guitars depends on the tuning. Since standard tuning is most commonly used, expositions of guitar chords emphasize the implementation of musical chords on guitars with standard tuning. The implementation of chords using particular tunings is a defining part of the literature on guitar chords, which is omitted in the abstract musical-theory of chords for all instruments.

For example, in the guitar (like other stringed instruments but unlike the piano), open-string notes are not fretted and so require less hand-motion. Thus chords that contain open notes are more easily played and hence more frequently played. Many of the most popular tunings—standard tuning, open tunings, and new standard tuning—are rich in the open notes used by popular chords.

Unlike the piano, the guitar has the same notes on different strings. Consequently, guitar players often double notes in chord, so increasing the volume of sound. Doubled notes also changes the chordal timbre: Having different "string widths, tensions and tunings, the doubled notes reinforce each other, like the doubled strings of a twelve-string guitar add chorusing and depth". Notes can be doubled at identical pitches or in different octaves. For triadic chords, doubling the third interval, which is either a major third or a minor third, clarifies whether the chord is major or minor.

A chord is inverted when the bass note is not the root note. If, in a particular tuning, chords cannot be played in root position, they can often be played in inverted positions. Additional chords can be generated with drop-2 (or drop-3) voicing, which are discussed for standard tuning's implementation of dominant seventh chords (below).

Fundamental chords

Standard tuning

In the standard guitar-tuning, one major-third interval is interjected amid four perfect-fourth intervals.

In standard tuning, the C-major chord has three shapes because of the irregular major-third between the G- and B-strings.

A six-string guitar has five musical-intervals between its consecutive strings. In standard tuning, the intervals are four perfect-fourths and one major-third, the comparatively irregular interval for the (G,B) pair. Consequently, standard tuning requires four chord-shapes for the major chords. There are separate chord-forms for chords having their root note on the third, fourth, fifth, and sixth strings. Of course, a beginner learns guitar by learning notes and chords, and irregularities make learning the guitar difficult—even more difficult than learning the formation of plural nouns in German, according to Gary Marcus. Nonetheless, most beginners use standard tuning.

Another feature of standard tuning is that the ordering of notes often differs from root position. Notes are often inverted or otherwise permuted, particularly with seventh chords in standard tuning, as discussed below.

Power chords: Fingerings

As previously discussed, each power chord has only one interval, a perfect fifth between the root note and the fifth. In standard tuning, the following fingerings are conventional:

• 

  E5

• 

  G5

• 

  G5

Triads

A barre chord ("E Major shape"), with the index finger used to bar the strings.

Triads are usually played with doubled notes, as the following examples illustrate.

Major

C major chord in open position

Commonly used major-chords are convenient to play in standard tuning, in which fundamental chords are available in open position, that is, the first three frets and additional open strings.

For the C major chord (C,E,G,), the conventional left-hand fingering doubles the C and E notes in the next octave; this fingering uses two open-notes, C and G:

• E on the first string
• C on the second string
• G on the third string
• E on the fourth string
• C on the fifth string
• Sixth string is not played.

For the other commonly used chords, the conventional fingerings also double notes and feature open-string notes:

• 

  A Major Chord

• 

  D Major Chord

• 

  E Major Chord

• 

  G Major Chord

Besides doubling the fifth note, the conventional E-major chord features a tripled bass-note.

The B major and F major chords are commonly played as barre chords, with the first finger depressing five–six strings.

• 

  B Major Chord

• 

  F Major Chord

B major chord has the same shape as the A major chord but it is located two frets further up the fretboard. The F major chord is the same shape as E major but it is located one fret further up the fretboard.

Minor

Minor chords (commonly notated as C-, Cm, Cmi or Cmin) are the same as major chords except that they have a minor third instead of a major third. This is a difference of one semitone.

To create F minor from the F major chord (in E major shape), the second finger should be lifted so that the third string plays onto the barre. Compare the F major to F minor:

• 

  F Major Chord

• 

  F Minor Chord

The other shapes can be modified as well:

Chord name	Fret numbers
E minor	[0 2 2 0 0 0]
A minor	[X 0 2 2 1 0]
D minor	[X X 0 2 3 1]

Dominant sevenths: Drop two

In standard tuning, the C7 chord has notes on frets 3-8. Covering six frets is difficult, and so C7 is rarely played. Instead, an "alternative voicing" is substituted.

Dominant seventh chord on C, played on guitar in open position  Play  and as a barre chord  Play .

As previously stated, a dominant seventh is a four-note chord combining a major chord and a minor seventh. For example, the C7 dominant seventh chord adds B♭ to the C-major chord (C,E,G). The naive chord (C,E,G,B♭) spans six frets from fret 3 to fret 8; such seventh chords "contain some pretty serious stretches in the left hand". An illustration shows a naive C7 chord, which would be extremely difficult to play, besides the open-position C7 chord that is conventional in standard tuning. The standard-tuning implementation of a C7 chord is a second-inversion C7 drop 2 chord, in which the second-highest note in a second inversion of the C7 chord is lowered by an octave. Beyond their conventional use for seventh chords, drop-two chords are used particularly in jazz guitar. Drop-two second-inversions are examples of openly voiced chords, which are typical of standard tuning and other popular guitar-tunings.

"Alternatively voiced" seventh chords are commonly played with standard tuning. A list of fret-number configurations for some common chords follows:

• E7:[020100]
• G7:[320001]
• A7:[X02020]
• B7:[X21202] (This B7 requires no barre, unlike the B major.)
• D7:[XX0212]

Other chord inversions

Already in basic guitar-playing, inversion is important for sevenths chords in standard tuning. It is also important for playing major chords.

In standard tuning, chord inversion depends on the bass note's string, and so there are three different forms for the inversion of each major chord, depending on the position of the irregular major-thirds interval between the G and D strings.

For example, if the note E (the open sixth string) is played over the A minor chord, then the chord would be [0 0 2 2 1 0]. This has the note E as its lowest tone instead of A. It is often written as Am/E, where the letter following the slash indicates the new bass note. However, in popular music it is usual to play inverted chords on the guitar when they are not part of the harmony, since the bass guitar can play the root pitch.

Alternate tunings

Main article: Guitar tunings#Alternative

Chords have consistent shapes everywhere on the fretboard for each regular tuning, for example, major-thirds (M3) tuning.

Chords can be shifted diagonally in regular tunings.

Chords vertically shift.

In major-thirds tuning, chords are inverted by raising notes by three strings on the same frets. The inversions of a C major chord are shown.

Major-thirds tuning repeats its notes after three strings.

There are many alternate tunings. These change the way chords are played, making some chords easier to play and others harder.

• Open tunings each allow a chord to be played by strumming the strings when "open", or while fretting no strings. The base chord consists of at least 3 notes and may include all the strings or a subset. The tuning is named for the base chord when played open, typically a major chord, and all similar chords in the chromatic scale can then be played by barring exactly one fret. Open tunings are common in blues and folk music, and they are used in the playing of slide and bottleneck guitars. Ry Cooder uses open tunings when he plays slide guitar.
• Drop tunings are common in hard rock and heavy metal music. In drop-D tuning, the standard tuning's E-string is tuned down to a D note. With drop-D tuning, the bottom three strings are tuned to a root-fifth-octave (D-A-D) tuning, which simplifies the playing of power chords.
• Regular tunings allow chord note-forms to be shifted all around the fretboard, on all six strings (unlike standard or other non-regular tunings). Knowing a few note-patterns—for example of the C major, C minor, and C7 chords—enables a guitarist to play all such chords.

Regular tunings

Main article: Regular tunings

See also: Repetitive tuning

Guitar chords are dramatically simplified by the class of alternative tunings called regular tunings. In each regular tuning, the musical intervals are the same for each pair of consecutive strings. Regular tunings include major-thirds (M3), all-fourths, augmented-fourths, and all-fifths tunings. For each regular tuning, chord patterns may be diagonally shifted down the fretboard, a property that simplifies beginners' learning of chords and that simplifies advanced players' improvisation. The diagonal shifting of a C major chord in M3 tuning appears in a diagram.

Further simplifications occur for the regular tunings that are repetitive, that is, which repeat their strings. For example, the E-G♯-c-e-g♯-c' M3 tuning repeats its octave after every two strings. Such repetition further simplifies the learning of chords and improvisation; This repetition results in two copies of the three open-strings' notes, each in a different octave. Similarly, the B-F-B-F-B-F augmented-fourths tuning repeats itself after one string.

A chord is inverted when the bass note is not the root note. Chord inversion is especially simple in M3 tuning. Chords are inverted simply by raising one or two notes by three strings; each raised note is played with the same finger as the original note. Inverted major and minor chords can be played on two frets in M3 tuning. In standard tuning, the shape of inversions depends on the involvement of the irregular major-third, and can involve four frets.

It is a challenge to adapt conventional guitar-chords to new standard tuning, which is based on all-fifths tuning.

Intermediate chords

After major and minor triads are learned, intermediate guitarists play seventh chords.

Tertian harmonization

Types of triads:  I ,  i ,  i^o ,  I⁺ 

Stacking of third intervals

The fundamental guitar-chords—major and minor triads and dominant sevenths—are tertian chords, which concatenate third intervals, with each such third being either major (M3) or minor (m3).

More triads: Diminished and augmented

As discussed above, major and minor triads are constructed by stacking thirds:

• The major triad concatenates (M3,m3), supplementing M3 with a perfect-fifth (P5) interval, and
• the minor triad concatenates (m3, M3), supplementing m3 with a P5 interval.

Similar tertian harmonization yields the remaining two triads:

• the diminished triad concatenates (m3,m3), supplementing m3 with a diminished-fifth interval, and
• the augmented triad concatenates (M3,M3), supplementing M3 with an augmented-fifth interval.

More sevenths: Major, minor, and (half-)diminished

Sevenths chords are constructed by stacking third intervals on the C-major scale. Fretboard diagrams for major-thirds tuning are shown.  Sevenths via tertian harmonization of major scale on C.mid 

Stacking thirds also constructs the most used seventh-chords. The most important seventh-chords concatenate a major triad with a third interval, supplementing it with a seventh interval:

1. The (dominant) major-minor seventh concatenates a major triad with another minor third, supplementing it with a minor-seventh interval.
2. The major seventh concatenates a major triad with a major third, supplementing it with a major-seventh interval.
3. The minor seventh concatenates a minor triad with a minor third, supplementing it with a minor-seventh interval.
4. The half-diminished seventh concatenates a diminished triad with a major third, supplementing it with a diminished-seventh interval.
5. The (fully) diminished seventh concatenates a diminished triad with a minor third, supplementing it with a diminished-seventh interval.

Four of these five seventh-chords—all but the diminished seventh—are constructed via the tertian harmonization of a major scale. As already stated,

• the major-minor seventh has the dominant V⁷ function.
• The major seventh plays the tonic (I7) and subdominant (IV⁷) roles;
• the minor seventh plays the ii⁷, iii⁷, and vi⁷ roles.
• the half-diminished seventh plays the vii^ø7 role.

While absent from the tertian harmonization of the major scale,

• the diminished seventh plays the vii^o7 role in the tertian harmonization of the harmonic minor scale.

Besides these five types there are many more seventh-chords, which are less used in the tonal harmony of the common-practice period.

An approximate "ranking by frequency of the seventh chords in major".
 Play V⁷  (Dominant),  ii⁷  (Minor),  vii^ø7  (Half-diminished),  IVM⁷  (Major),  vi⁷ ,  IM⁷ , or  iii⁷ .

When playing seventh chords, guitarists often play only subset of notes from the chord. The fifth is often omitted. When a guitar is accompanied by a bass, the guitarist may omit the bass note from a chord. As discussed earlier, the third of a triad is doubled to emphasize its major or minor quality; similarly, the third of a seventh is doubled to emphasize its major or minor quality. The most frequent seventh is the dominant seventh; the minor, half-diminished, and major sevenths are also popular.

Chord progression: Circle of fifths

Sevenths chords arising in the tertian harmonization of the C-major scale, arranged by the circle of perfect fifths (perfect fourths). Fretboard diagrams for major-thirds tuning are shown.  FifthsC.mid 

The previously discussed I-IV-V chord progressions of major triads is a subsequence of the circle progression, which ascends by perfect fourths and descends by perfect fifths: Perfect fifths and perfect fourths are inverse intervals, because one reaches the same pitch class by either ascending by a perfect fourth (five semitones) or descending by a perfect fifth (seven semitones). For example, the jazz standard Autumn Leaves contains the iv⁷-VII⁷-VIM⁷-ii^ø7-i circle-of-fifths chord-progression; its sevenths occur in the tertian harmonization in sevenths of the minor scale. Other subsequences of the fifths-circle chord-progression are used in music. In particular, the ii-V-I progression is the most important chord progression in jazz music.

Specific tunings

Standard tuning: Minor and major sevenths

Besides the dominant seventh chords discussed above, other seventh chords—especially minor seventh chords and major seventh chords—are used in guitar music.

Minor seventh chords have the following fingerings in standard tuning:

• Dm7: [XX0211]
• Em7: [020000]
• Am7: [X02010]
• Bm7: [X20202]
• F♯m7: [202220]or ([XX2222] Also an A/F♯ Chord)

Major seventh chords have the following fingerings in standard tuning:

• Cmaj7: [X32000]
• Dmaj7: [XX0222]
• Emaj7: [021100]
• Fmaj7: [103210]
• Gmaj7: [320002]
• Amaj7: [X02120]

Major-thirds tuning

In major-thirds (M3) tuning, the chromatic scale is arranged on three consecutive strings in four consecutive frets. This four-fret arrangement facilitates the left-hand technique for classical (Spanish) guitar: For each hand position of four frets, the hand is stationary and the fingers move, each finger being responsible for exactly one fret. Consequently, three hand-positions (covering frets 1–4, 5–8, and 9–12) partition the fingerboard of classical guitar, which has exactly 12 frets.

Only two or three frets are needed for the guitar chords—major, minor, and dominant sevenths—which are emphasized in introductions to guitar-playing and to the fundamentals of music. Each major and minor chord can be played on exactly two successive frets on exactly three successive strings, and therefore each needs only two fingers. Other chords—seconds, fourths, sevenths, and ninths—are played on only three successive frets.

Advanced chords and harmony

Extended chords

Commonly voiced with only four notes in open position, ninth and eleventh chords often play a dominant (V) role.  Play 9th (left)   Play 11th

As their categorical name suggests, extended chords indeed extend seventh chords by stacking one or more additional third-intervals, successively constructing ninth, eleventh, and finally thirteenth chords; thirteenth chords contain all seven notes of the diatonic scale. In closed position, extended chords contain dissonant intervals or may sound supersaturated, particularly thirteenth chords with their seven notes. Consequently, extended chords are often played with the omission of one or more tones, especially the fifth and often the third, as already noted for seventh chords; similarly, eleventh chords often omit the ninth, and thirteenth chords the ninth or eleventh. Often, the third is raised an octave, mimicking its position in the root's sequence of harmonics.

Dominant ninth chords were used by Beethoven, and eleventh chords appeared in impressionistic music. Thirteenth chords appeared in the twentieth century. Extended chords appear in many musical genres, including jazz, funk, rhythm and blues, and progressive rock.

Alternative harmonies

Scales and modes

Conventional music uses diatonic harmony, the major and minor keys and major and minor scales, as sketched above. Jazz guitarists must be fluent with jazz chords and also with many scales and modes; "of all the forms of music, jazz ... demands the highest level of musicianship—in terms of both theory and technique".

Whole-tone scales were used by King Crimson for the title track on its Red album of 1974; whole-tone scales were also used by King Crimson guitarist Robert Fripp on "Fractured".

Beyond tertian harmony

Disliking the sound of thirds (in equal-temperament tuning), Robert Fripp builds chords with perfect intervals in his new standard tuning.

Quartal and quintal harmony

Chords are also systematically constructed by stacking not only thirds but also fourths and fifths, supplementing tertian major–minor harmony with quartal and quintal harmonies. Quartal and quintal harmonies are used by guitarists who play jazz, folk, and rock music.

Quartal harmony has been used in jazz by guitarists such as Jim Hall (especially on Sonny Rollins's The Bridge), George Benson ("Skydive"), Kenny Burrell ("So What"), and Wes Montgomery ("Little Sunflower").

Harmonies based on fourths and fifths also appear in folk guitar. On her 1968 debut album Song to a Seagull, Joni Mitchell used both quartal and quintal harmony in "Dawntreader", and she used quintal harmony in "Seagull".

Quartal and quintal harmonies also appear in alternate tunings. It is easier to finger the chords that are based on perfect fifths in new standard tuning than in standard tuning. New standard tuning was invented by Robert Fripp, a guitarist for King Crimson. Preferring to base chords on perfect intervals—especially octaves, fifths, and fourths—Fripp often avoids minor thirds and especially major thirds, which are sharp in equal temperament tuning (in comparison to thirds in just intonation).

Alternative harmonies can also be generated by stacking second intervals (major or minor).

Sequences of thirds and seconds

The circle of fifths was discussed in the section on intermediate guitar-chords. Other progressions are also based on sequences of third intervals; progressions are occasionally based on sequences of second intervals.

Conclusion

While the literature on guitar chords relies on conventional musical-theory, it discusses topics specific to the guitar (and other stringed instruments). The guitar offers several ways to play most notes, and also to play a note in a nearby octave. These features allow guitarists flexibility in playing notes and hence chords, for timbre and fingering ease. Guitarists often duplicate notes in chords, to increase the volume and change the tone and timbre. Inversions and open voicings allow guitarists to play chords in particular tunings, when the closed voicing would be difficult or impossible.

Additional discussions of chords appear in the extensive literature for guitarists.

See also

• Mel Bay's Deluxe Encyclopedia of Guitar Chords

References

Bibliography

• Denyer, Ralph (1992). "Playing the guitar, pp. 65-160, and The chord dictionary, pp. 225-249". The guitar handbook. Special contributors Isaac Guillory and Alastair M. Crawford (Fully revised and updated ed.). London and Sydney: Pan Books. ISBN 0-330-32750-X. 
• Duckworth, William (2007). A creative approach to music fundamentals: Includes keyboard and guitar insert (ninth ed.). 2005928009: Thomson Schirmer. pp. 1–384. ISBN 0-495-09093-X. 
• Everett, Walter (2008). The foundations of rock: From "Blue Suede Shoes" to "Suite: Judy Blue Eyes". Oxford University Press. pp. 1–442. ISBN 978-0-19-531024-5. 
• Griewank, Andreas (1 January 2010), Tuning guitars and reading music in major thirds, Matheon preprints 695, Rosestr. 3a, 12524 Berlin, Germany: DFG research center "MATHEON, Mathematics for key technologies" Berlin, Postscript file and Pdf file 
• Kolb, Tom (2005). Music theory. Hal Leonard Guitar Method. Hal Leonard Corporation. pp. 1–104. ISBN 0-634-06651-X. 
• Kostka, Stefan; Payne, Dorothy; Almén, Byron (2013). Tonal harmony with an introduction to twentieth-century music (seventh ed.). New York: McGraw-Hill. ISBN 978-0-07-131828-0. 
• Macon, Edward L. (1997). Rocking the classics: English progressive rock and the counterculture. Oxford and New York: Oxford University. ISBN 0-19-509887-0. 
• Marcus, Gary (2012). Guitar zero: The science of learning to be musical. Oneworld. ISBN 9781851689323. 
• Mead, David (2002). Chords and scales for guitarists. London: Bobcat Books Limited: SMT. ISBN 978-1860744327. 
• Persichetti, Vincent (1961). Twentieth-century harmony: Creative aspects and practice. New York: W. W. Norton. ISBN 0-393-09539-8. OCLC 398434. 
• Peterson, Jonathon (2002). "Tuning in thirds: A new approach to playing leads to a new kind of guitar". American Lutherie: The Quarterly Journal of the Guild of American Luthiers (8222 South Park Avenue, Tacoma WA 98408: USA.: The Guild of American Luthiers) 72 (Winter): 36–43. ISSN 1041-7176. Retrieved 9 October 2012. 
• Roche, Eric (2004). "3 One-man band, 4 Exploring the fingerboard, 5 Thinking outside the box". The acoustic guitar Bible. London: Bobcat Books Limited, SMT. pp. 74–109, 110–150, and 151–178. ISBN 186074432X. 
• Schmid, Will; Kolb, Tom (2002). "Chord chart". Guitar method: Book 1. Hal Leonard Guitar Method (second ed.). Hal Leonard Corporation. p. 47. ISBN 0-7935-3392-9. 
• Sethares, Bill (2001). "Regular tunings" (pdf). Alternate tuning guide. Madison, Wisconsin: University of Wisconsin; Department of Electrical Engineering. pp. 52–67. Retrieved 19 May 2012. 
• Sethares, Bill (10 January 2009) [2001]. Alternate tuning guide (pdf). Madison, Wisconsin: University of Wisconsin; Department of Electrical Engineering. Retrieved 19 May 2012. 
• Sethares, William A. (18 May 2012). "Alternate tuning guide". Madison, Wisconsin: University of Wisconsin; Department of Electrical Engineering. Retrieved 8 December 2012. 

Further reading

• Bay, William (18 June 2008). Deluxe guitar chord encyclopedia: Case-size edition. Mel Bay Publications. ISBN 978-0-7866-7522-7. Retrieved 4 April 2012. 
• Patt, Ralph (1962). Guitar chord dictionary. H. Adler. pp. 1–43. 

External links

• Guitar at the Open Directory Project
• Guitar Lessons at the Open Directory Project