If you know and like Gregorian chant, you will adore this music.

The Formschneider print contains over 350 plainsong-based polyphonic motets for most feasts of the Mass Proper. Brown (1976) described it as a “comprehensive compendium of virtually all devices, manners and styles prevalent at the time”.

Each motet is based on the chant for that Proper item. Depending on the season of the church year Proper items appear or disappear, e.g., the alleluias are replaced by tracts during Lent. Sometimes the chant appears verbatim in phrases, sometimes it is paraphrased. In some motets one voice predominantly carries the chant while the other voices support it. In others, the chant appears in all voices at different times.

The shorter motets (introits, alleluias, communions) are suitable for liturgical services, generally lasting between 1-4 minutes in length. The introits and alleluias are equally suitable for concert performance. The sequences are the tour de force of the Choralis Constantinus, due to their length and rhythmic complexity. Victims of the liturgical reforms of the Council of Trent, sequences might last for 10-12 minutes. When coupled with the adjoining alleluia the performance would be alleluia, alleluia verse, sequence, alleluia – quite the concert within the liturgical service! Isaac set every other verse in polyphony. Mahrt (1970) theorized that missing verses were probably improvisations of the chant on the organ. The late Dr. Mary Berry of Cambridge University and noted Gregorian chant scholar was convinced that chant performance at that time often took the form of long-held notes sung by the choir while the organist improvised. Berry and Mahrt’s theories are supported in the physical evidence left by Hans Buchner, organist at the Constance cathedral during the composition of the CC. Buchner and Isaac were connected as the former was a student of Paul Hofhaimer, organist for Maximilian’s chapel. Three sequences that occur in the CC – always polyphonic settings of the even-numbered  verses – are in the same keys as Buchner’s settings of the odd-numbered verses of the same sequences.

Audio Recording

As announced here and in other media, Carus-Verlag has issued a recording by Markus Utz and his ensemble cantissimo of much of this music. To obtain a copy either contact ensemble cantissimo here or Carus-Verlag here.