In the early 14th century the ars nova began as a novel movement whose chief champion was Philippe de Vitry. About 1325, he employed the term "ars nova" as the title of a treatise, which unfortunately deals primarily with the notational rather than the musical innovations of the period. More illuminating from a general point of view are the discussions in the "Speculum musicae," whose author, Jacques de Liege, gives extremely interesting information regarding the stylistic contrast between the ars antiqua and the ars nova.
The main achievement of the ars nova was the conquest of new territory in the field of rhythm and meter. While the music of the late 13th century was dominated by the principle of triple division (modus perfectum and tempus perfectum) the binary divisions were now admitted, so that the composer could choose from a variety of meters.
Another important difference is the replacement of the rhythmic formula
e
q by its inversion,
q e.
The latter rhythmic formula prevails
in the music of Philippe de Vitry and the greatest 14th-century French
composer Guilluame Machaut.
Another important aspect of the motets of this period is the use of isorhythm, regularly in the tenor and occasionally in the upper parts as well.
Even more radically new is the style of Machaut's secular works, the polyphonic ballades, rondeaux, and virelais, most of which are probably of a later date than his motets. These secular pieces show free contrapuntal texture, supple rhythms, and expressive melodies, and generally bear the stamp of high refinement, delicacy, individuality, spontaneous creation, and even personal feeling, so that one is almost tempted to speak of a "14th-century romanticism."
The harmonic style of the ars nova shows some advance over that of the ars antiqua insofar as thirds are introduced more frequently. Of special interest is the treatment of dissonances, which frequently reminds one of the dissonant counterpoint of modern composers. The polyphonic texture starts and converges in perfect consonances, mainly octaves, fourths, and fifths, while in between the lines move with a remarkable degree of individuality and independence from harmonic considerations.
Probably the most famous Italian composer of the ars nova was Francesco Landini.
(See also the Articles entries: Ars Nova in Italy and Ars Nova in France)