Notational Characteristics
One of the techniques of the ars subtilior involved using red notes, or "coloration", where the red notes indicate an alteration of note values by one third.
Manuscripts of works in the ars subtilior occasionally were themselves in unusual and expressive shapes, as a form of eye music. As well as Baude Cordier's circular canon and the heart-shaped score shown above, Jacob Senleches's La Harpe de melodie is written in the shape of a harp.
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