Introduction Gregorian chant OTTAVIANO PETRVCCI
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Introduction to the page Gregorian chant in modern notation


Introduction to Renaissance sheet music

Renaissance sheet music

Mean tone temperament

Gregorian plainchant in modern staff notation

Bicinia from Obrecht to Mozart

Post Petrucci





Catholic services are distinguished in two main types: the Holy Mass and the Hours, Office or choral prayer.

I present pieces from the first group only on this website page.

The mass is arranged as follows:

* Introitus, with - psalm verse, opening

+ Kyrie

+ Gloria

1-st lecture

* Graduale

2-nd lecture

* Alleluia, during Lent: * Tractus

Lecture of the Gospel

+ Credo

* Offertorium, during offering of bread and wine

- Praefatie, introduction to the Canon Prayer and Consecration

+ Sanctus and Benedictus

Canon Prayer and Consecration

- Pater noster

+ Agnus Dei

Distribution of the Holy Communion

* Communio with - psalm

Dismission and blessing.

The pieces marked + form the Ordinarium or Ordinary chant. The Ordinarium may be sung in the same way every day. The pieces with a - are recited on simple tones, just like the psalms of the Introitus and Communio. Innumerous polyphone settings have been composed for the Ordinary since circa 1300.  The pieces marked * form the Proprium Chant. Each day or feast in the Ecclesiastical Year has its own Proprium.

The Proprium chant is the subject matter of the page Gregorian chant in modern notation.

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1. Origin

2. Reform circa 1600

3. Reconstruction


1. Origin

Gregorian chant derives its name from Gregory the Great (Pope 590-604) with whom its origin is associated since the eighth century. His own writings, however, do not give any reference to musical matters and only scanty information on liturgical activities in general. Nor does Isidorus of Sevilla (writing in 638) tell anything about this subject in connection with Gregory. Liturgical regulations are indeed ascribed to other popes and abbots, among whom Bonifacius II (530-532: a cycle of songs through the year, cantilena anni circoli). A schola with a prior cantorum (precentor) is mentioned first only half a century after Pope Gregory. This institute is essential for singing the Prorium. Other Christian liturgical singing is known since the fourth century, a.o. the hymns by the Milanese bishop and church father Ambrosius.

There is not the faintest evidence for origins of Gregorian plainchant, in either the music of the classic Greek, or the Roman antiquity, or in the Jewish music.

Several countries in Western Europe gave birth to different styles and repertories of plainchant. The most imortant are the Beneventan (Southern Italy), the Roman , the Mozarabic (in Spain) the Gallican (in France) and the Ambrosian (in Northern Italy). The latter is still in use in the bishopric of Milan.

Two different developments mainly took place in the time of Charlemagne.

The first was the introduction of Byzantine musical theory in Western Europe. This subject will be treated beneath, under Modi.

The second development was the aspiration of Pippine the Short (751-768) and his son Charlemagne (768-814) to unify their empire from Northern Italy to Northern Spain, including the newly conquered parts of Germany, involving cultural and religious aspects. So Roman clerics were invited to France and Frankish clerics went to Rome to teach and learn the way plainchant was sung in Rome. In the same period many new liturgical songs were composed. Consequently the need made itself felt to write down the music. About 900 the so called neumatic notation had been developed. Neuma (Greek) means head or hand movement. This notation restrained itself to the rhythm, the pitches were notated in mutual relationship only: high, low, equally, etc.

These neumes were in use for simple hymns, the ordinary of the mass (Kyrie, etc.) and psalmody as well as for the more complicated proprium chant. It is nearly certain that the latter was sung by a solo virtuoso and not by a choir.

Only gradually a system was developed to notate the pitch on one,later more horizontal lines, and ayt the same time the rhythmical notation eventually waned. Gradually all notes gained the same appearance of black squares and the same duration, this way becoming real plainchant. One of the characteristics of Gregorian chant, the extended series of melodies sung to one syllable, lost its significance this way. They were however performed for centuries afterwards.


2. Reform about 1600

Only the Concily of Trent (1545-1563) ended in a decision to simplify the existing church music. The decision implied the simplification of the polyphonic music in use since about 1300 for the Ordinarium of the mass, but also of the plainchant of the Proprium. This task was originally commissioned to Giovanni Pierluigi da Palestrina in 1577, only to be  completed by his successors. They published the Editio Medicea in 1614 and 1615. This development is generally considered to be regrettable in the manuals.

The simplified melodies however harmonise extraordinarily well with the polyphonic masses of Josquin, Palestrina, Mozart or Bruckner, which continued to be performed after the Concily. In my opinion the simplification has been executed in a extraordinary logical and musical way. The reconstructed original chant of the 8-th - 10-th century, to be discussed beneath, does not lend itself to be performed in one service in combination with Western polyphony, either medieval or modern.

New plainchant was composed in the seventeenth century, like the well known Credo III and the hymn Rorate caeli that is sung during Advent. They were composed only in the simple way. Nowadays there are also composed new compositions in Gregorian chant, for instance my composition Quod chorus vatum, a hymn on text by Hrabanus Maurus (ca 800) for the vesper of St. Mary's Purification on the page Post Petrucci.


3. Reconstruction

In the nineteenth century the Benedictine monks of Solesmes (France) began reconstructing the early medieval Gregorian chant. The name of André Mocquereau is connected with this. He made a classification of the two most important manuscript families from the 9-th and 10-th centuries, as far as they contained neumes. The most important manuscripts of these groups are a manuscript preserved in the library of the abbey of St Gallen, Switzerland, dating from the end of the 9-th century and a manuscript in the municipal library of Laon, France and its derivatives. Besides he consulted a manuscript from the 11-the century in the library of the Medical Faculty of Montpellier. This manuscript contains both the neumatic signs and a notation in letters for the pitches. This manuscript served as a Rosetta Stone for the original chant melodies. The manuscripts from Sankt-Gallen (nrs. 359, 339, 376 en 390/391), Laon (239, 12, 226b and 240) and from Montpellier (H 159) are accessable on internet, see also the page Links.

The most well-known results of this work are: (a) the Graduale Romanum, with the liturgical chant for the masses throughout the church year, (b), the Antiphonale Monasticum, with the Office and (c) a combination of both that got the name Liber Usualis ("users book").These books have been introduced in the church in the beginning of the 20-th century, after a several decads long struggle between promotors of the way of performance of the reconstructed medieval chant and sceptic and conservative scholars (among whom respected specialists) supported by the commercially involved reprinter of the Editio Medicea. You may found here the Liber Usualis in square notation and the Liber Usualis in modern notation.

The sceptics and conservatives were partially right, arguing that the new Graduale contained many errors in the transcription, and that the interpretation of the rhythmical signs was far from certain and partially even wrong. Nevertheless the Graduale remained in use for nearly the whole of the 20-th century.

By comparing the manuscripts systematically another Benedictine monk, Eugène Cardine, succeeded in finding a reliable point of departure for the reconstruction of the rhythm, in a way he called the semiological method. His publication Sémiologie Grégorienne dates from 1970 (English translation by Robert M. Fowles, Solesmes 1982).

The existing print of the Graduale Romanum, enlarged with neumatic signs of the two most important manuscript families was edited under the name Graduale Triplex (= Threefold Gradual) in 1979. The two different series of neumes were added in different colors above and under the original square staffs. Regrettably the errors in the transcription from the Montpellier manuscript were not corrected. Furthermore, only the Proprium chant was handled this way, and the editors did not  reanalyse or reconstruct the Ordinary.  Only a few manuscripts have been transmitted containing the Ordinary provided with neumatic signs.

The errors in the proprium have however been restored by a Dutchman Chris Hakkenes, in his publication Graduale Lagal (The Hague 1984, with an introduction in Latin and English). He invented a new way of rendering neumes and notes, and produced a complete edition of the Gradual according to the semiological method.

Parts of the corrected Graduale may also be found on the website of the Choralschola Freiburg (Germany) Gregor und Taube (Gregory and Dove). The site is in German and Latin. This edition does not render all rhythmical differences. But the neumes from the Sankt Gallen family of manuscripts have mostly been added above the amended square notes. This edition, based on the Graduale restitutum, published in the German periodical Beiträge zur Gregorianik, will gradually be completed.

More and more Gregorian choirs converted to the semiological way of singing since about 1990.

A comprehensive history of Gregorian chant is: David Hiley, Western Plainchant, Oxford 1993. See also the page  Links.

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The Grogorian chant system has 8 moods (modi, singular: modus). Classical music, on the contrary, only has three (major, minor harmonically and minor melodically) which may be transposed to any pitch, because we are used to equal temperature. The Gregorian moods in the non- transposed form use the white keys of the keyboard only, but including  the si/b lowered to b-flat/sa. The Gregorian modi have been taken from the Byzantine musical theory, that called this system the Octoechos (= "The Eight").

The mood of every chant is indicated by a number preceding the first staff. The odd numbers are authentic (=original) and the even numbers are plagal (=derivative).  1 and 2 have the tonic and final on re, 3 and 4 on mi, 5 and 6 on fa and 7 and 8 on sol. As explained above the moods do not have a fixed pitch, but for each individual song the most appropriate pitch was chosen.

The original names of the moods are the Greek ordinal numbers: proterus, deuterus, tritus and tetrardus, each of them resp. authenticus and plagalis. Tetrardus plagalis = modus 8.

The melodies of the four authentic moods use the whole tone scale above the tonic. The four plagal ones make less use of the higher tones, the reason being that the dominant of the authentic moods are the fifth and of the plagal moods the third. (This disagrees with the twelve church moods in use since the sixteenth century). Besides the si is avoided as dominant, and it has the inclination to shift to the do. This concerns of course the authentic third mood (tonic mi) and the plagal eighth mood (tonic sol), and it may be seen in the pieces presented here, the Introit Si iniquitates (3) and the Tract Qui confidunt (8). In both of the dominant seems to hover between si and do.

Furthermore, the Gregorian chant is inclined to lower the 4-th step of the 5-th mood, the si again, to sa. This actually produces the F major scale of classical Western music. In the Gradual Christus factus est (5) the si only occurs in combination with the do immediately before or after it, and even then mostly lowered to sa. It is generally assumed that Gregorian chant originally had a tone scale on do, agreeing with our C major. But Western music paid too much respect to the Byzantine theory accepting the Octoechos, and so had to do by using a modified 5-th mood instead.

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As a consequence of the semiological interpretation another interpretation has come into being, the mensuralistic. The term is to be found at first in 1927, opposite egalitarian. The latter means that all notes have the same duration in principle.

The modern mensuralistic theory interprets the note groups with  seemingly different values according to the rules of semiology and, next, brought back to note groups with a duration of one unit of time or beat (tempus or chronos) and multiples of it.

The idea originated from comparing the original neumatic signs with the medieval Byzantine and cognate music notations. By the way, medieval Byzantine music is no longer in use in the Eastern churches, its present liturgical music only dates back to the eighteenth century.

A recent summary of the mensuralistic interpretation may be found in the articles cited in the Dutch text, and I regret that I do not know an English equivalent to those texts. There is, however, a summary on the website of J. van Biezen. The websites devoted to Gregorian plainchant (see the page Links) do not pay attention to notational problems or possibilities, as far as I know. Geert Maessen performs some Gregorian chants with his choir and illustrated with neumes according to Sankt-Gallen on youtube.

This theory may be subject to criticism, but as a whole it enables a consistent and practical interpretation. Besides it is much more accessible to non-semiologists.

That is why I made the transcriptions on this wesite according to this method.

The pre-eminent objection against the mere semiological performance practice is the following. It took Cardine a lot of effort to in define the significance and relationships of the neumatic signs. They do not mean exactly the same in all positions and combinations. He found that some signs had a duration of one tempus and that the most other ones take half a tempus.

According to the semiologists however it is not allowed to sing that way, as that would be mensuralism: only slight differences in duration between long and short notes are acceptable. Another objection is that the semiology knows at least three diferent types of short notes which are hardly or not distinguished in meaning.

It is weak that the semiologists do not produce any intrinsic objection against mensuralism.

Hakkenes (see under Short history) consequently gives the differences in duration approaching the mensuralistic way. He does not distinguish the different types of short neumatic signs. He renders some of them in apart signs (oriscus, strophae) but he did not know an interpretation for them.

The mensuralists have also succeeded in finding a plausible interpretation also of the short notes. The differences mostly concern different forms of graces: shakes and appogiaturas.

Notes of double duration, present beyond doubt in the Sankt-Gallen manuscripts, are generally not rendered by Hakkenes.

The objection against the mensuralist method is that not all short notes are reducible to binaries.The mensuralists explain this by interpreting the superfluous notes as graces.  They find support for this thesis in the ninth-century musical theory and in the comparison with other neumatic systems, especially again the Byzantine one. They give the use of triplets as an alternative. In the cases that an interpretation with appogiaturas seemed to be less possible I applied them as well.

I made my transcriptions from the Sankt-Gallen neumes, which vary from the Laon family in many details. I corrected the square black notes of the Graduale print according to Hakkenes. A description of my method of transcription, with tables, is available in  Transcription of neums in the manuscipt family of Sankt Gallen to modern notation .

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The average chorus member is able to perform appogiaturas but not shakes. This only proves that the proprium songs were meant to be sung by a soloist. There are, however, hardly any professional singers who are interested in the repertory.

It is very sad that nobody is performing this music adequately at the moment that we think to have at least two ways to do it.

But there are many experienced amateurs playing melody instruments who badly need new repertory. Modern composers are evidently hardly interested in writing attractive music with an accessible notation for this numerous group of performers.

As a player of the alto and tenor recorder I tried whether transcriptions of Gregorian plainchant would "work". Indeed they do. Of course plainchant is meant to be vocal. The breathing technique of the alto recorder agrees more with the breathing technique of singing voices than any other instrument.

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