|Notes||This notation, which is the oldest surviving example of a polyphonic hymn notation, appears amongst unique accretions to a version of the anonymous music treatise Musica enchiriadis usually dated to the late ninth century. The Daseian notation, so-called because most of the signs derive from the Greek aspirant sign (the daseia), is principally found within the Enchiriadis group of treatises - Musica enchiriadis, Scolica enchiriadis and Commemoratio brevis. |
The similarities between the three melodies given for Gratuletur omnis are strong for the opening half line (syllables 1-8). In the Naples and Klosterneuburg manuscripts this opening melodic contour is repeated for the first eight syllables of the third line and similar melodic contours are again traced. Elsewhere within the strophe correspondences in melodic contour are harder to identify.
|Melody||The lower voice follows the principles outlined in chapter seventeen of the Musica Enchiriadis for adding an extra (organal) voice at the interval of a fourth, whereby the organal voice is forbidden to descend beneath the 'tetrardus' (in this case the initial 'c'). According to this rule, the lower voice remains on 'c' until movement in fourths can be established, returning to unison in the second half of the line since the interval of a fourth cannot be maintained there without descending beneath the 'tetrardus' tone.|