Organum: a second voice composed to decorate an original
plainchant.
The early polyphony that we call organum was probably improvised
before it was written down. Motion in parallel intervals and heterophony
appear in many musical cultures and were probably practiced in Europe.
Polyphony
was described in Musica enchiriadis and Scholica enchiriadis,
a treatise and a textbook from ca. 900. In this early organum, an added voice (organal
voice or vox organalis) appears below a chant melody (principal voice or voix
principalis), moving either in parallel motion at the interval of a fourth
or fifth (parallel organum) or in a mix of parallel and oblique motion (organum
with oblique motion).
--A History of Western Music, fifth edition, by Grout/Palisca
Polyphonic settings of
Latin poems called versus are the earliest polyphony not based on chant.
Manuscripts for these types of polyphony use score notation (one part
above the other, with notes that sound together aligned vertically), but do not
indicate rhythm.
Organum now usually refers to
polyphony used in
liturgical music from the late 9th century to c. 1250.
Originally, it was a
neumatic
and
melismatic chant section by the choir at the beginning and end of a piece.
The number of voices contained in a section of organum determines its
nomenclature (ie: 2 voices is Organum duplum, three is Organum triplum four is
Organum quadruplum etc).
Several types of organum that developed the high middle ages:
-
Parallel Organum – Strict homophony with parallel 4ths, 5ths, and 8vas. It is
syllabic, meaning there is only one note per syllable.
- Modified Parallel Organum –
Each phrase begins in unison, spreads to parallel 4ths and contracts again to
unison. It is syllabic.
- Free Organum – A style of note
against note. It is not melismatic between
the two voices, but it is melismatic between the text and music of each
individual voice. The phrases end on a unison or 8va, and the voices are
independent within phrases. In free organum, the added voice usually sings above
the chant, although the voices may cross.
- Florid Organum - A style where the chant is sustained in long notes in the lower voice (called the
tenor),
while the upper voice sings from one to many notes above each note of the
tenor. This style was called organum, organum duplum (double
organum), or organum purum (pure organum).
From florid organum,
polyphonic music progressed to what was known as Notre Dame organum.
Notre Dame Organum.
Notre Dame organum originated, as its name suggests, in Notre Dame cathedral
in Paris in the late eleventh or early twelfth century and continued to be
written there until the fourteenth century.. The musicians at the Notre Dame school were the first to
work out how to notate more than two voices by fixing a definite rhythm. The style
spread across western Europe.
The most famous (and probably best) composers of organum were Leonin,
composer of Magnus Liber Organi (including Graduals and Alleluias
he had improved upon), and Perotin, who modified and improved on
Leonin's work by adding better clausulae. These men were the first organum
composers identified by name.
Leonin was born in about 1135 CE. His compositions were based on the Gregorian
chants. The original chant
served as the foundation and a second voice (the descant), was added to
the original chant.
Perotin (Perotinus) was one of Leonin's students and appears to have been
born between 1155 and 1160. During his studies with Leonin, he made some
important revisions to Leonin's Magnus Liber Organi
and developed some ideas of his own about polyphony. To the additional voice
part that Leonin added, Perotin added a third and fourth vocal part Perotin named the three additional parts the duplum, triplum, and quadruplum.
All three of these voice parts were based on and written above the original
chant.
There are three types of Notre Dame Organum:
- Organum purum.
The most simple organum. It has no rhythm and consists of a tenor voice, which sings the original
plainchant and a duplum.
- Copula.
Still a very simple organum. The
top voice or voices in this case do have rhythm, but the original chant is still
without any meter.
- Discant
The most advanced form of Notre Dame organum. Both the chant and the organal voices
have rhythm. Although the original setting
of the chant was not rhythmic, composers maintained its integrity by using the
same pitches in the same order, often repeating the pitc hes for one syllable
or word over and over.
From the thirteenth century, the use of organum in liturgical music declined sharply.
http://w3.rz-berlin.mpg.de/cmp/musical_history.html
http://www.ced.appstate.edu/intercollege/3850/studwork/medieval/guide/exa/organum.htm
http://www.vanderbilt.edu/Blair/Courses/MUSL242/f98/willisb3.htm
http://keyboardtimes.com/mh/Chapter03/chapter03summary.htm
http://www.hypermusic.ca/comp/leonin.html
http://www.planetpapers.com/Assets/268.php
http://www.lawrence.edu/fac/koopmajo/antiquity.html
http://www.maternalheart.com/library/chant_history.htm
http://www.vanderbilt.edu/Blair/Courses/MUSL242/chrish~1.htm