This collection includes 56 choral sources from the 14th to the 18th century for the celebration of the divine service. Among them are numerous choir books, which are either artistically illuminated and handwritten or represent rare prints from the 16th and 17th centuries.

The digitised sources are of great importance for music and liturgical studies and especially for art history (remarkable book decoration) and thus represent important monuments of Austrian cultural heritage.

A look at the antiphonaries of the Poor Clares and Franciscans of Graz in the 15th century reveals a familiar picture. In addition to the usual standard repertoire of antiphons and responsories, we find common verse offices in the order such as Trinity, Antonius, Clara, Stigmata Sancti Francisci, Franciscus and Ludovicus Rex. The oldest gradual from Maria Lankowitz (before 1332) is written in a somewhat imprecise square notation. The traces of a lively, constantly renewing liturgy in the later additions are interesting.

The chant manuscripts from the 18th century are of particular liturgical interest. In contrast to the prints, they are usually a faithful reflection of actual liturgical practice and allow a faithful reconstruction of the services celebrated with chant in an overall view. This concerns the extent of what was actually sung in the individual hymns and allows an insight into those domestic customs according to which the rank of a festival becomes visible in the gradation of the singing.

In addition to the chant manuscripts, there are also a number of chant prints - gradualia and antiphonaries - which provide an insight into chant production. The books, which have generally only survived in a few copies, come from Venetian printers such as Cieras, Balleoni, Pezzana, from the Mayr printing house in Salzburg or from Leopold Voigt in Vienna.

According to the post-Tridentine liturgical books, the volumes are usually in two parts; the general gradual of the Roman liturgy, for example, is accompanied by a Franciscan appendix, often also from other printing years. In addition to the Franciscan calendar, these graduals and antiphonals also contain all the original chants in the appendix, including the numerous newly composed offices for those saints of the order who have been canonised since the end of the Middle Ages.