Unison in the context of "Monophony"

A part in music refers to a component of a musical composition. Because there are multiple ways to separate these components, there are several contradictory senses in which the word "part" is used:

• any individual melody (or voice), whether vocal or instrumental, that can be abstracted as continuous and independent from other notes being performed simultaneously in polyphony. Within the music played by a single pianist, one can often identify outer parts (the top and bottom parts) or an inner part (those in between). On the other hand, within a choir, "outer parts" and "inner parts" would refer to music performed by different singers. (See § Polyphony and part-writing)
• the musical instructions for any individual instrument or voice (often given as a handwritten, printed, or digitized document) of sheet music (as opposed to the full score which shows all parts of the ensemble in the same document). A musician's part usually does not contain instructions for the other players in the ensemble, only instructions for that individual.
• the music played by any group of musicians who all perform together for a given piece; in a symphony orchestra, a dozen or more cello players may all play "the same part" even if they each have their own physical copy of the music. This part may be in unison or may be harmonized, and may even sometimes contain counter-melodies within it. A percussion part may sometimes only contain rhythm. This sense of "part" does not require a written copy of the music; a bass player in a rock band "plays the bass part" even if there is no written version of the song.
• a section in the large-scale form of a piece. (See § Musical form)

Organum (/ˈɔːrɡənəm/) is, in general, a plainchant melody with at least one added voice to enhance the harmony, developed in the Middle Ages. Depending on the mode and form of the chant, a supporting bass line (or bourdon) may be sung on the same text, the melody may be followed in parallel motion (parallel organum), or a combination of both of these techniques may be employed. As no real independent second voice exists, this is a form of heterophony. In its earliest stages, organum involved two musical voices: a Gregorian chant melody, and the same melody transposed by a consonant interval, usually a perfect fifth or fourth. In these cases the composition often began and ended on a unison, the added voice keeping to the initial tone until the first part has reached a fifth or fourth, from where both voices proceeded in parallel harmony, with the reverse process at the end. Organum was originally improvised; while one singer performed a notated melody (the vox principalis), another singer—singing "by ear"—provided the unnotated second melody (the vox organalis). Over time, composers began to write added parts that were not just simple transpositions, thus creating true polyphony.

In organology, a course is either one string or two or more adjacent strings that are closely spaced relative to the other strings, and typically played as a single string. The strings in each multiple-string course are typically tuned in unison or an octave.

Normally, the term course is used to refer to a single string only on an instrument that also has multi-string courses. For example, a nine-string baroque guitar has five courses: most are two-string courses but sometimes the lowest or the highest consists of a single string.

In music, an octave (Latin: octavus: eighth) or perfect octave (sometimes called the diapason) is an interval between two notes, one having twice the frequency of vibration of the other. The octave relationship is a natural phenomenon that has been referred to as the "basic miracle of music", the use of which is "common in most musical systems". The interval between the first and second harmonics of the harmonic series is an octave. In Western music notation, notes separated by an octave (or multiple octaves) have the same name and are of the same pitch class.

To emphasize that it is one of the perfect intervals (including unison, perfect fourth, and perfect fifth), the octave is designated P8. Other interval qualities are also possible, though rare. The octave above or below an indicated note is sometimes abbreviated 8 or 8 (Italian: all'ottava), 8 bassa (Italian: all'ottava bassa, sometimes also 8), or simply 8 for the octave in the direction indicated by placing this mark above or below the staff.

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"."

A mandolin (Italian: mandolino, pronounced [mandoˈliːno]; literally "small mandola") is a stringed musical instrument in the lute family and is generally plucked with a pick. It most commonly has four courses of doubled strings tuned in unison, thus giving a total of eight strings. A variety of string types are used, with steel strings being the most common and usually the least expensive. The courses are typically tuned in an interval of perfect fifths, with the same tuning as a violin (G3, D4, A4, E5). Also, like the violin, it is the soprano member of a family that includes the mandola, octave mandolin, mandocello and mandobass.

There are many styles of mandolin, but the three most common types are the Neapolitan or round-backed mandolin, the archtop mandolin and the flat-backed mandolin. The round-backed version has a deep bottom, constructed of strips of wood, glued together into a bowl. The archtop, also known as the carved-top mandolin, has an arched top and a shallower, arched back both carved out of wood. The flat-backed mandolin uses thin sheets of wood for the body, braced on the inside for strength in a similar manner to a guitar. Each style of instrument has its own sound quality and is associated with particular styles of music. Neapolitan mandolins feature prominently in European classical music and in traditional music like the Andean music of Peru. Archtop instruments are common in American folk music and bluegrass music. Flat-backed instruments are commonly used in Irish, British, and Brazilian folk music, and Mexican estudiantinas.

Phase music is a form of music that uses phasing as a primary compositional process. It is an approach to musical composition that is often associated with minimal music, as it shares similar characteristics, but some commentators prefer to treat phase music as a separate category. Phasing is a compositional technique in which the same part (a repetitive phrase) is played on two musical instruments, in steady but not identical tempo. Thus, the two instruments gradually shift out of unison, creating first a slight echo as one instrument plays a little behind the other, then a doubling effect with each note heard twice, then a complex ringing effect, and eventually coming back through doubling and echo into unison.

Phasing is the rhythmic equivalent of cycling through the phase of two waveforms as in phasing. The tempi of the two instruments are almost identical, so that both parts are perceived as being in the same tempo: the changes only separate the parts gradually. In some cases, especially live performance where gradual separation is extremely difficult, phasing is accomplished by periodically inserting an extra note (or temporarily removing one) into the phrase of one of the two players playing the same repeated phrase, thus shifting the phase by a single beat at a time, rather than gradually.

Process music is music that arises from a process. It may make that process audible to the listener, or the process may be concealed.

Primarily begun in the 1960s, diverse composers have employed divergent methods and styles of process. "A 'musical process' as Christensen defines it is a highly complex dynamic phenomenon involving audible structures that evolve in the course of the musical performance ... 2nd order audible developments, i.e., audible developments within audible developments". These processes may involve specific systems of choosing and arranging notes through pitch and time, often involving a long term change with a limited amount of musical material, or transformations of musical events that are already relatively complex in themselves.

A schismatic temperament is a musical tuning system that results from tempering the schisma of 32805:32768 (1.9537 cents) to a unison. It is also called the schismic temperament, Helmholtz temperament, or quasi-Pythagorean temperament.