In music, metre (British spelling) or meter (American spelling) refers to regularly recurring patterns and accents such as downbeats and beats. Unlike rhythm, metric onsets are not necessarily sounded, but are nevertheless implied by the performer (or performers) and expected by the listener.
A variety of systems exist throughout the world for organising and playing metrical music, such as the Indian system of tala and similar systems in Arabic and African music.
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Musique concrète (French pronunciation: [myzik kɔ̃kʁɛt]; lit. 'concrete music') is a type of music composition that utilizes recorded sounds as raw material. Sounds are often modified through the application of audio signal processing and tape music techniques, and may be assembled into a form of sound collage. It can feature sounds derived from recordings of musical instruments, the human voice, and the natural environment, as well as those created using sound synthesis and computer-based digital signal processing. Compositions in this idiom are not restricted to the normal musical rules of melody, harmony, rhythm, and metre. The technique exploits acousmatic sound, such that sound identities can often be intentionally obscured or appear unconnected to their source cause.
The theoretical basis of musique concrète as a compositional practice was developed by French composer Pierre Schaeffer, beginning in the early 1940s. It was largely an attempt to differentiate between music based on the abstract medium of notation and that created using so-called sound objects (French: l'objet sonore). By the early 1950s, musique concrète was contrasted with "pure" elektronische Musik as then developed in West Germany – based solely on the use of electronically produced sounds rather than recorded sounds – but the distinction has since been blurred such that the term "electronic music" covers both meanings. Schaeffer's work resulted in the establishment of France's Groupe de Recherches de Musique Concrète (GRMC), which attracted important figures including Pierre Henry, Luc Ferrari, Pierre Boulez, Karlheinz Stockhausen, Edgard Varèse, and Iannis Xenakis. From the late 1960s onward, and particularly in France, the term acousmatic music (French: musique acousmatique) was used in reference to fixed media compositions that utilized both musique concrète-based techniques and live sound spatialisation.
Aristoxenus of Tarentum (Greek: Ἀριστόξενος ὁ Ταραντῖνος; born c. 375, fl. 335 BC) was a Greek Peripatetic philosopher, and a pupil of Aristotle. Most of his writings, which dealt with philosophy, ethics and music, have been lost, but one musical treatise, Elements of Harmony (Greek: Ἁρμονικὰ στοιχεῖα; Latin: Elementa harmonica), survives incomplete, as well as some fragments concerning rhythm and meter. The Elements is the chief source of our knowledge of ancient Greek music.
A time signature (also known as meter signature, metre signature, and measure signature) is an indication in music notation that specifies how many note values of a particular type fit into each measure (bar). The time signature indicates the meter of a musical movement at the bar level.
In a music score the time signature appears as two stacked numerals, such as
4 (spoken as four–four time), or a time symbol, such as 
(spoken as common time). It immediately follows the key signature (or if there is no key signature, the clef symbol). A mid-score time signature, usually immediately following a barline, indicates a change of meter.
Musical symbols are marks and symbols in musical notation that indicate various aspects of how a piece of music is to be performed. There are symbols to communicate information about many musical elements, including pitch, duration, dynamics, or articulation of musical notes; tempo, metre, form (e.g., whether sections are repeated), and details about specific playing techniques (e.g., which fingers, keys, or pedals are to be used, whether a string instrument should be bowed or plucked, or whether the bow of a string instrument should move up or down).
A chorale is the name of several related musical forms originating in the music genre of the Lutheran chorale:
The chorale originated when Martin Luther translated sacred songs into the vernacular language (German), contrary to the established practice of church music near the end of the first quarter of the 16th century. The first hymnals according to Luther's new method were published in 1524. Luther and his followers not only wrote metrical hymn lyrics, but also composed metrical musical settings for these texts. This music was partially based on established melodies of church hymns and known secular songs. In the 17th century the repertoire was enriched with more choral and organ settings of the chorale tunes. By the end of the century a four-part setting for SATB voices had become the standard for the choral settings, while the congregational singing of chorales was tending towards monody with an instrumental accompaniment. The prolific creation of new Lutheran chorale tunes ended around that time.
A madrigal is a form of secular vocal music most typical of the Renaissance (15th–16th centuries) and early Baroque (1580–1650) periods, although revisited by some later European composers. The polyphonic madrigal is unaccompanied, and the number of voices varies from two to eight, but the form usually features three to six voices, whilst the metre of the madrigal varies between two or three tercets, followed by one or two couplets. Unlike verse-repeating strophic forms sung to the same music, most madrigals are through-composed, featuring different music for each stanza of lyrics, whereby the composer expresses the emotions contained in each line and in single words of the poem being sung.
Madrigals written by Italianized Franco–Flemish composers in the 1520s partly originated from the three-to-four voice frottola (1470–1530); partly from composers' renewed interest in poetry written in vernacular Italian; partly from the stylistic influence of the French chanson; and from the polyphony of the motet (13th–16th centuries). The technical contrast between the musical forms is in the frottola consisting of music set to stanzas of text, whilst the madrigal is through-composed, a work with different music for different stanzas. As a composition, the madrigal of the Renaissance is unlike the two-to-three voice Italian Trecento madrigal (1300–1370) of the 14th century, having in common only the name madrigal, which some have suggested derives from the Latin matricalis (maternal) denoting musical work in service to the mother church or from the post-classical Latin matricalis (maternal, simple, primitive). Other sources note that the word "madrigal" comes from the Hebrew word "madriga" meaning "step" (the "-al" suffix of the word also is Hebrew, in this case meaning "in the style of") and describes the step-like progression of the tune. The early Christians having been Jews are believed to have brought the musical style into the Christian/Byzantine liturgy and, from there, into Gregorian chant and from there it made its way into secular song.
In tap dancing, jazz, and blues, stop-time is an accompaniment pattern interrupting, or stopping, the normal time and featuring regular accented attacks on the first beat of each or every other measure, alternating with silence or instrumental solos. Stop-time occasionally appears in ragtime music. The characteristics of stop-time are heavy accents, frequent rests, and a stereotyped cadential pattern. Stop-timing may create the impression that the tempo has changed, though it has not, as the soloist continues without accompaniment. Stop-time is common in African-American popular music including R&B, soul music, and led to the development of the break in hip hop.
Stop-time is, according to Samuel A. Floyd Jr., "a musical device in which the forward flow of the music stops, or seems to stop, suspended in a rhythmic unison, while in some cases an improvising instrumentalist or singer continues solo with the forward flow of the meter and tempo. Such stop-time moments are sometimes repeated, creating an illusion of starting and stopping, as, for example, in Scott Joplin's "The Ragtime Dance" and Jelly Roll Morton's "King Porter Stomp"."