De la Enciclopedia Cecilia
- Normas del Vaticano acerca de la interpretación de los neumas
- Normas para la correcta pronunciación del latín
- Propios de algunas misas (vgr: semana de pascua, fiestas de los santos)
- Cantos, plegarias y lecturas del Oficio divino
- Texto en latin de lecturas de la Sda. Escritura
The Liber usualis is a book of commonly-used Gregorian chants compiled by the monks of the Abbey of Solesmes in France.
This 1,900-page book contains most versions of the ordinary chants for the Mass (Kyrie, Gloria, Credo, Sanctus, and Agnus Dei), as well as the common chants for the Divine Office (a priest's daily prayers) and for every commonly celebrated feast of the Church Year (including more than two hundred pages for Holy Week alone). The "usual book" or "common book" also contains chants for specific rituals, such as baptisms, weddings, funerals, ordinations, and benediction. This modal, monophonic Latin music has been sung in the Catholic Church since at least the sixth century and through the present day.
An extensive introduction explains how to read and interpret the medieval musical notation (square notation of neums or neumes). A complete index makes it easy to find specific pieces.
The Liber was first edited in 1896 by Solesmes abbot Dom André Mocquereau (1849–1930). After the Second Vatican Ecumenical Council (opened by Pope John XXIII in 1962) allowed in the constitution on the liturgy Sacrosanctum Concilium the vernacular (local language) to be used in Church rites, its use has decreased, although the same council mandated that Gregorian Chant should retain "pride of place" in the liturgy [Sacrosanctum Concilium] para. 116. Gregorian chants are still sung in most monasteries and some churches and in performances by groups dedicated to its preservation.
The Liber usualis does not reflect the new order of chant propers for the Masses of the church year by order of the Council. Furthermore, research on the notation of the Gregorian chant accomplished after the Liber's publication has shown that a lot more information about the rhythm and articulation of the chants can be drawn from the adiastematic neumes than from the square notation alone. The Liber therefore is nowadays considered outdated. Its place has been taken by other books like the Graduale Romanum (1974). However, the versions found in the Liber Usualis, or other versions in the manuscripts upon which the Liber was based, are still most commonly sung in primarily musical (i.e., non-liturgical) performances of chant.
Due to its shortcomings, the Liber Usualis has been out of print since 1964, which meant that for most of the 1970s to the '90s, it was not easy to find. Recently, the book has been reprinted and is easily available.