The medieval music includes hymns and chants which are examples of monophonic music. Monophony means music with single "part" and a "part" typically means a single vocal melody, but it could mean a single melody on an instrument of one kind or another. Important example of monophonic music is the troubadour repertory...
Plain chants (contus plonus) are also examples of monophony. This may be realized as just one note at a time, or with the same note duplicated at the octave . If the entire melody is sung by two voices or a choir with an interval between the notes or in unison, it is also said to be in monophony. Towards the end of the nineth century, singers in some monasteries began exploring the idea of music beyond strict monophony. Due to Catholic Church, they did this by approaching harmony in the simplest way possible: by adding one additional voice to the original chant melody that moved along in parallel motion.
This new age in Medieval music was devoted to this idea of developing harmony and polyphony. Officially, we call this time period the Ars Antiqua (13th century) or “The Old Art.” Polyphony means music with more than one part, and so this indicates simultaneous notes as opposed to music with just one voice (monophony) or music with one dominant melodic voice accompanied with chords which is called homophony. The term is usually used to refer to music of the late Middle Ages and Renaissance in western musical tradition.
The first appearance of polyphonic music form is named organum. Early organums are joined the tenor voice by the fifth below. Musica enchiriadis is an anonymous musical treatise from the 9th century. It is the first attempt to establish a system of rules for polyphony in classical music. The author shows how consonant intervals should be used in order to compose or improvise polyphonic music in early Middle Ages. Several examples of organum, an early style of note-against-note polyphony, are included in the treatise.
There are some types of organum. Parallel organum is an organum that includes the original chant melody which is called vox prihclipalis and vox organalis which is an exact parallel motion a fifth or fourth below. However, in Musica Enrichiriadis augmented fourths which are also called both tritone and diabidus in musica are forbidden since it sounds evil and creates an unexplainable feeling in us. Augmented fourth is composed of three whole tones such as B flat and F flat. In case of confronting tritons, Musica Enrichiriadis suggest that to produce organum that was not strictly parallel. The singers performing the organal added voice must remain on the previous note in order not to sounding tritone.
If one part increases with the tones while other part decreases, it is called contrary organum. Oblique organum is called if there is a stable tone below the original chant. If the two parts moving the same way in notes but the space between tones are different, this type of organum is called similar organum.
Winchester Troper is a manuscript contains over 160 examples of 2-part organum pieces, possible written by Wulfstan of Winchester. From this manuscript we may come to the conclusion that the organums were written down only to aid to remember the organum and make easier to memorize them. ‘’Christe Redemptor’’ may be an example of Winchester Troper.
By the late 11th century, the organum has greater independence and predominance are known today as free organum. Free organum is a free mixture of contrary,oblique,parallel and similar motion usually remains the unison,fourth,fifth and octave.’’Alleluia, jestus ut palma’’ from the treatise ‘’Ad Faciendum Organum’’ includes examples of parallel,oblique,similar and contrary organums.
In early 12th century, three manuscripts held in the Abbey of St. Martial at Limoges in the duchy of Aquitaine, today known as Aqutanian Polyphony. While organum is sung by upper part, tenor (the lower voice ) sings a chant. The lower voice sings much more slowly than the upper voice, this style is called as florid organum.’’O primus homo curruit’’ from Medieval Christmas album is an example of florid organum. If one to three notes in the upper part occur at the same time as one note in the lower part, discant style occurs. ’’O primus homo corruit’’ is an example of Aquitanian polyphony and ‘’Ad superni regis decus’’ includes examples of discant.
There was a group of composers that lived at the Notre Dame Cathedral in Paris. This group spearheaded the new movement towards early polyphony and mastered the art of organum. They are now known as the Notre Dame school of polyphony.( around 1160-1250) Therefore only two specific names are now recognized as being members of this Notre Dame School: Leonin and Perotin mentioned by anonymous 4. Notre Dame created a more complex style including the first body of music for more than two independent voices. Tenor voice at the bottom became a drum voice. Sometimes there was no tenor part at all, just two or three organums which is called Clausalve. The motet was first developed during this period , which is one of the most frequently encountered types of composition in the Magnus Liber Organi – the big book of organum. These motets have different texts even different languages for each part. These motets’ names are the combinations of the first lines of each text sang by different parts. This additional parts are called duplum and triplum. Adam de la Halle’s ‘’De ma dame vient/Dieus, comment porroie/Omnes’’ can be shown as example of motet. If upper and lower parts exchange the words, we call it as rota. ‘’Sumer is icumen’’ is an example of it.
There was no rhythm in chants mostly because composers didn’t want to intervene to God’s words. However, in 13th century, Perotin found six basic patterns known today as rhythmic modes. Composers started incorporating the use of rhythmic modes, clear patters of long notes (longs) + short notes(breves), with all of the upper voices moving together which was a major step towards rhythmic development.