Method of holding the lyre and stopping the strings.
In De institutione musica Boethius sets out the theoretical structure of Greek music, which contrasts fixed and movable strings (known as hestotes and kinumenoi to the Greeks), and tells us of three kinds of music: I. the stable, eternal, cosmic music, II. human music and III. instrumental or vocal music. Bragod’s first essays in setting 6th and 7th century poetry use the six-stringed lyre tuned CDEFGA. In this setting of Awdl LI, strings C, D and G are considered the fixed strings (‘I’s), E, F and A are the movable strings (‘O’s) and Korffiniwr IIOO IOII, one of the mesurau or measures, has been borrowed from the later middle ages as a compositional basis.
As with Peis Dinogat, the natural, upward, melodic stresses at the ends of phrases and lines have been observed in the music. The ideas set out by Boethius, largely a gathering together of Pythagorean thought, are still alive in the music in the Robert ap Huw manuscript and the cerdd dant treatises, especially the division of the seven notes of the scale into fixed and movable sets (cyweirdannau a lleddfdannau), the fixed set or cyweirdannau corresponding to the tuning of the crwth.
The intervals of the cyweirdannau conform to the Pythagorean ratio – 12 : 9 : 8 : 6. In his paper, Canu Aneirin Awdl LI, Dr. G. R. Isaac tells us that this poetry ‘…has nothing to do with accentual metrics,… but is a structure of responding syllable and word patterns, carefully regulated, balanced and intertwined with patterns of responding phonemes (i.e. in rhyme, consonance etc.).