In modern musical notation and tuning, an enharmonic equivalent is a note, interval, or key signature, equivalent to some other note, interval, or key signature but "spelled", or named differently. Thus, the enharmonic spelling of a written note, interval, or chord is an alternative way to write that note, interval, or chord. For example, in twelve-tone equal temperament, the notes C♯ and D♭ are enharmonic notes. Namely, they are the same key on a keyboard, thus they are identical in pitch, although they have different names and different roles in harmony and chord progressions. Arbitrary amounts of accidentals can produce further enharmonic equivalents, such as B, although these are much rarer and have less practical use. In other words, if two notes have the same pitch but are represented by different letter names and accidentals, they are enharmonic. "Enharmonic intervals are intervals with the same sound that are spelled differently…, of course, from enharmonic tones."Prior to this modern meaning, "enharmonic" referred to notes that were close in pitch—closer than the smallest step of a diatonic scale—but not identical in pitch, such as F♯ and a flattened note such as G♭, as in an enharmonic scale.
"Enharmonic equivalence is peculiar to post-tonal theory." "Much music since at least the 18th century, exploits enharmonic equivalence for purposes of modulation and this requires that enharmonic equivalents in fact be equivalent." Some key signatures have an enharmonic equivalent that represents a scale identical in sound but spelled differently. The number of sharps and flats of two enharmonically equivalent keys sum to twelve. For example, the key of B major, with 5 sharps, is enharmonically equivalent to the key of C♭ major with 7 flats, 5 + 7 = 12. Keys past 7 sharps or flats exist only theoretically and not in practice; the enharmonic keys are six pairs, three major and three minor: B major/C♭ major, G♯ minor/A♭ minor, F♯ major/G♭ major, D♯ minor/E♭ minor, C♯ major/D♭ major and A♯ minor/B♭ minor. There are no works composed in keys that require double sharps or double flats in the key signature. In practice, musicians learn and practice 15 major and 15 minor keys, three more than 12 due to the enharmonic spellings.
Enharmonic equivalents can be used to improve the readability of a line of music. For example, a sequence of notes is more read as "ascending" or "descending" if the noteheads are on different positions on the staff. Doing so may reduce the number of accidentals that must be used. Thus, in the key of B♭ major, the sequence B♭-B♮-B♭ is more read using the enharmonic spelling C♭ instead of B♮. For example, the intervals of a minor sixth on C, on B♯, an augmented fifth on C are all enharmonic intervals Play; the most common enharmonic intervals are the augmented fourth and diminished fifth, or tritone, for example C–F♯ = C–G♭. Enharmonic equivalence is not to be confused with octave equivalence, nor are enharmonic intervals to be confused with inverted or compound intervals. In principle, the modern musical use of the word enharmonic to mean identical tones is correct only in equal temperament, where the octave is divided into 12 equal semitones. In other tuning systems, enharmonic associations can be perceived by listeners and exploited by composers.
In Pythagorean tuning, all pitches are generated from a series of justly tuned perfect fifths, each with a frequency ratio of 3 to 2. If the first note in the series is an A♭, the thirteenth note in the series, G♯ is higher than the seventh octave of the A♭ by a small interval called a Pythagorean comma; this interval is expressed mathematically as: twelve fifths seven octaves = 12 2 7 = 3 12 2 19 = 531 441 524 288 = 1.013 643 264... ≈ 23.46 cents In quarter-comma meantone, on the other hand, consider G♯ and A♭. Call middle C's frequency x. High C has a frequency of 2x; the quarter-comma meantone has just major thirds, which means major thirds with a frequency ratio of 4 to 5. To form a just major third with the C above it, A♭ and high C must be in the ratio 4 to 5, so A♭ needs to have the frequency 4 5 = 8 5 x = 1.6 x. To form a just major third above E, however, G♯ needs to form the ratio 5 to 4 with E, which, in turn, needs to form the ratio 5 to 4 with C, thus the frequency of G♯ is 2 x = 25 16 x = 1.5625 x Thus, G♯ and A♭ are not the same note.
The difference is the interval called the enharmonic diesis, or a frequency ratio of 128/125. On a piano tuned in equal temperament, both G♯ and A♭ are played by striking the same key, so both hav
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A clef is a musical symbol used to indicate the pitch of written notes. Placed on a stave, it indicates the pitch of the notes on one of the lines; this line serves as a reference point by which the names of the notes on any other line or space of the stave may be determined. There are three forms of clef used in modern music notation: F, C, G; each form assigns its reference note to a line depending on its placement on the stave. Once one of these clefs has been placed on one of the lines of the stave, the other lines and spaces are read in relation to it; the use of different clefs makes it possible to write music for all instruments and voices, regardless of differences in tessitura. Because the modern stave has only five lines, it is not possible to represent all pitches playable by the orchestra with only one clef with the use of ledger lines; the use of different clefs for various instruments and voices allows each part to be written comfortably on the stave with a minimum of ledger lines.
To this end, the G-clef is used for high parts, the C-clef for middle parts, the F-clef for low parts—with the notable exception of transposing parts, which are written at a pitch different from their sound even in a different octave. To facilitate writing for different tessituras, any of the clefs may theoretically be placed on any line of the stave; the further down on the stave a clef is positioned, the higher the tessitura. Since there are five lines on the stave, three clefs, it might seem that there would be fifteen possible clefs. Six of these, are redundant clefs; that leaves nine possible distinct clefs, all of which have been used historically: the G-clef on the two bottom lines, the F-clef on the three top lines, the C-clef on any line of the stave except the topmost, earning the name of "movable C-clef". Each of these clefs has a different name based on the tessitura. In modern music, only four clefs are used regularly: treble clef, bass clef, alto clef, tenor clef. Of these, the treble and bass clefs are by far the most common.
The tenor clef is used for the upper register of several instruments that use bass clef, while the alto is only used by the viola and a few other instruments. Here follows a complete list of the clefs, along with a list of instruments and voice parts notated with them; each clef is shown in its proper position on the stave, followed by its reference note.† Where the G-clef is placed on the second line of the stave, it is called the treble clef. This is the most common clef used today, the first clef that those studying music learn, the only G-clef still in use. For this reason, the terms G-clef and treble clef are seen as synonymous; the treble clef was used to mark a treble, or pre-pubescent, voice part. Among the instruments that use treble clef are the violin, oboe, cor anglais, all clarinets, all saxophones, trumpet, vibraphone, mandolin, recorder. Treble clef is the upper stave of the grand stave used for keyboard instruments, it is sometimes used, along with tenor clef, for the highest notes played by bass-clef instruments such as the cello, double bass and trombone.
The viola sometimes uses treble clef for high notes. Treble clef is used for the soprano, mezzo-soprano, alto and tenor voices; when sung, a tenor singer will sing the piece an octave lower, is written using an octave clef or double-treble clef. † In the seventeenth and eighteenth centuries, a special clef was used for violin music that published in France. For this reason it is known as the French clef or French violin clef, although it was more used for flute music; the G-clef is placed on the first line of the stave and is identical to the bass clef transposed up two octaves. When the F-clef is placed on the fourth line, it is called the bass clef; this is the only F-clef used today so that the terms "F-clef" and "bass clef" are regarded as synonymous. This clef is used for the cello, double bass, bass guitar, contrabassoon, baritone horn and timpani, it is used for the lowest notes of the horn, for the baritone and bass voices. Tenor voice is notated in bass clef when the bass are written on the same stave.
Bass clef is the bottom clef in the grand stave for keyboard instruments. The contrabassoon, double bass, electric bass sound an octave lower than the written pitch. † When the F-clef is placed on the third line, it is called the baritone clef. This clef was used for the left hand of keyboard music as well as the baritone part in vocal music; the baritone clef has the less common variant as a C clef placed on the 5th line, equivalent. † Where the F-clef is placed on the fifth line, it is called the sub-bass clef. It is identical to the treble clef transposed down 2 octaves; this clef was used by Johannes Ockeghem and Heinrich Schütz to write low bass parts, making a late appearance in Ba
Music notation or musical notation is any system used to visually represent aurally perceived music played with instruments or sung by the human voice through the use of written, printed, or otherwise-produced symbols. Types and methods of notation have varied between cultures and throughout history, much information about ancient music notation is fragmentary. In the same time period, such as in the 2010s, different styles of music and different cultures use different music notation methods; the symbols used include ancient symbols and modern symbols made upon any media such as symbols cut into stone, made in clay tablets, made using a pen on papyrus or parchment or manuscript paper. Although many ancient cultures used symbols to represent melodies and rhythms, none of them were comprehensive, this has limited today's understanding of their music; the seeds of what would become modern western notation were sown in medieval Europe, starting with the Catholic Church's goal for ecclesiastical uniformity.
The church began notating plainchant melodies so that the same chants could be used throughout the church. Music notation developed further in the Baroque music eras. In the classical period and the Romantic music era, notation continued to develop as new musical instrument technologies were developed. In the contemporary classical music of the 20th and 21st century, music notation has continued to develop, with the introduction of graphical notation by some modern composers and the use, since the 1980s, of computer-based score writer programs for notating music. Music notation has been adapted to many kinds of music, including classical music, popular music, traditional music; the earliest form of musical notation can be found in a cuneiform tablet, created at Nippur, in Babylonia, in about 1400 BC. The tablet represents fragmentary instructions for performing music, that the music was composed in harmonies of thirds, that it was written using a diatonic scale. A tablet from about 1250 BC shows a more developed form of notation.
Although the interpretation of the notation system is still controversial, it is clear that the notation indicates the names of strings on a lyre, the tuning of, described in other tablets. Although they are fragmentary, these tablets represent the earliest notated melodies found anywhere in the world. Ancient Greek musical notation was in use from at least the 6th century BC until the 4th century AD; the notation consists of symbols placed above text syllables. An example of a complete composition is the Seikilos epitaph, variously dated between the 2nd century BC to the 1st century AD. Three hymns by Mesomedes of Crete exist in manuscript; the Delphic Hymns, dated to the 2nd century BC use this notation, but they are not preserved. Ancient Greek notation appears to have fallen out of use around the time of the Decline of the Western Roman Empire. Byzantine music has survived as music for court ceremonies, including vocal religious music, it is not known if it is based on the monodic modal singing and instrumental music of Ancient Greece.
Greek theoretical categories played a key role to understand and transmit Byzantine music the tradition of Damascus had a strong impact on the pre-Islamic Near East comparable to Persian music. Unlike Western notation Byzantine neumes always indicate modal steps in relation to a clef or modal key; this key or the incipit of a common melody was enough to indicate a certain melodic model given within the echos. Despite ekphonetic notation further early melodic notation developed not earlier than between the 9th and the 10th century. Like the Greek alphabet notational signs are ordered left to right; the question of rhythm was based on cheironomia, well-known melodical phrases given by gestures of the choirleaders, which existed once as part of an oral tradition. Today the main difference between Western and Eastern neumes is that Eastern notation symbols are differential rather than absolute, i.e. they indicate pitch steps, the musicians know to deduce from the score and the note they are singing presently, which correct interval is meant.
These step symbols themselves, or better "phonic neumes", resemble brush strokes and are colloquially called gántzoi in Modern Greek. Notes as pitch classes or modal keys are represented in written form only between these neumes. In modern notation they serve as an optional reminder and modal and tempo directions have been added, if necessary. In Papadic notation medial signatures meant a temporary change into another echos; the so-called "great signs" were once related to cheironomic signs. Since Chrysanthos of Madytos there are seven standard note names used for "solfège" pá, vú, ghá, dhē, ké, zō, nē, while the older practice still used t
In classical music from Western culture, a third is a musical interval encompassing three staff positions, the major third is a third spanning four semitones. Along with the minor third, the major third is one of two occurring thirds, it is qualified as major because it is the larger of the two: the major third spans four semitones, the minor third three. For example, the interval from C to E is a major third, as the note E lies four semitones above C, there are three staff positions from C to E. Diminished and augmented thirds span the same number of staff positions, but consist of a different number of semitones; the major third may be derived from the harmonic series as the interval between the fourth and fifth harmonics. The major scale is so named because of the presence of this interval between its tonic and mediant scale degrees; the major chord takes its name from the presence of this interval built on the chord's root. A major third is different in different musical tunings: in just intonation corresponds to a pitch ratio of 5:4 or 386.31 cents.
The older concept of a ditone made a dissonantly wide major third with the ratio 81:64. The septimal major third is 9:7, the undecimal major third is 14:11, the tridecimal major third is 13:10. A helpful way to recognize a major third is to hum the first two notes of "Kumbaya" or of "When the Saints Go Marching In". A descending major third is heard at the starts of "Goodnight, Ladies" and "Swing Low, Sweet Chariot". In equal temperament three major thirds in a row are equal to an octave; this is sometimes called the "circle of thirds". In just intonation, three 5:4 major thirds are less than an octave. For example, three 5:4 major thirds from C is B♯; the difference between this just-tuned B♯ and C, like that between G♯ and A♭, is called a diesis, about 41 cents. The major third is classed as an imperfect consonance and is considered one of the most consonant intervals after the unison, perfect fifth, perfect fourth. In the common practice period, thirds were considered interesting and dynamic consonances along with their inverses the sixths, but in medieval times they were considered dissonances unusable in a stable final sonority.
A diminished fourth is enharmonically equivalent to a major third. For example, B–D♯ is a major third. B–E♭ occurs in the C harmonic minor scale; the major third is used in guitar tunings. For the standard tuning, only the interval between the 3rd and 2nd strings is a major third. In an alternative tuning, the major-thirds tuning, each of the intervals are major thirds. Decade, compound just major third Ear training List of meantone intervals
A chord, in music, is any harmonic set of pitches consisting of multiple notes that are heard as if sounding simultaneously. For many practical and theoretical purposes and broken chords, or sequences of chord tones, may be considered as chords. Chords and sequences of chords are used in modern West African and Oceanic music, Western classical music, Western popular music. In tonal Western classical music, the most encountered chords are triads, so called because they consist of three distinct notes: the root note, intervals of a third and a fifth above the root note. Chords with more than three notes include added tone chords, extended chords and tone clusters, which are used in contemporary classical music and other genres. A series of chords is called a chord progression. One example of a used chord progression in Western traditional music and blues is the 12 bar blues progression. Although any chord may in principle be followed by any other chord, certain patterns of chords are more common in Western music, some patterns have been accepted as establishing the key in common-practice harmony—notably the resolution of a dominant chord to a tonic chord.
To describe this, Western music theory has developed the practice of numbering chords using Roman numerals to represent the number of diatonic steps up from the tonic note of the scale. Common ways of notating or representing chords in Western music include Roman numerals, the Nashville number system, figured bass, macro symbols, chord charts; the English word chord derives from Middle English cord, a shortening of accord in the original sense of agreement and harmonious sound. A sequence of chords is known as a chord harmonic progression; these are used in Western music. A chord progression "aims for a definite goal" of establishing a tonality founded on a key, root or tonic chord; the study of harmony involves chords and chord progressions and the principles of connection that govern them. Ottó Károlyi writes that, "Two or more notes sounded are known as a chord," though, since instances of any given note in different octaves may be taken as the same note, it is more precise for the purposes of analysis to speak of distinct pitch classes.
Furthermore, as three notes are needed to define any common chord, three is taken as the minimum number of notes that form a definite chord. Hence, Andrew Surmani, for example, states, "When three or more notes are sounded together, the combination is called a chord." George T. Jones agrees: "Two tones sounding together are termed an interval, while three or more tones are called a chord." According to Monath. However, sonorities of two pitches, or single-note melodies, are heard as implying chords. A simple example of two notes being interpreted as a chord is when the root and third are played but the fifth is omitted. In the key of C major, if the music comes to rest on the two notes G and B, most listeners will hear this as a G major chord. Since a chord may be understood as such when all its notes are not audible, there has been some academic discussion regarding the point at which a group of notes may be called a chord. Jean-Jacques Nattiez explains that, "We can encounter'pure chords' in a musical work," such as in the Promenade of Modest Mussorgsky's Pictures at an Exhibition but, "Often, we must go from a textual given to a more abstract representation of the chords being used," as in Claude Debussy's Première arabesque.
In the medieval era, early Christian hymns featured organum, with chord progressions and harmony an incidental result of the emphasis on melodic lines during the medieval and Renaissance. The Baroque period, the 17th and 18th centuries, began to feature the major and minor scale based tonal system and harmony, including chord progressions and circle progressions, it was in the Baroque period that the accompaniment of melodies with chords was developed, as in figured bass, the familiar cadences. In the Renaissance, certain dissonant sonorities that suggest the dominant seventh occurred with frequency. In the Baroque period, the dominant seventh proper was introduced and was in constant use in the Classical and Romantic periods; the leading-tone seventh remains in use. Composers began to use nondominant seventh chords in the Baroque period, they became frequent in the Classical period, gave way to altered dominants in the Romantic period, underwent a resurgence in the Post-Romantic and Impressionistic period.
The Romantic period, the 19th century, featured increased chromaticism. Composers began to use secondary dominants in the Baroque, they became common in the Romantic period. Many contemporary popular Western genres continue to rely on simple diatonic harmony, though far from universally: notable exceptions include the music of film scores, which use chromatic, atonal or post-tonal harmony, modern jazz, in which chords may include up to seven notes; when referring to chords that do not function as harmony, such as in atonal music, the term "sonority" is used to avoid any tonal implications of the word "chord". Chords can be represent