Guillaume Costeley

Costeley's surviving music amounts to about 100 chansons, as well as three motets and a fantasy for organ. Everything that he wrote can be dated to the period between 1554 and 1569. His motets, his only known sacred works, are for four and five voices and show the influence of Jean Maillard. A connection between the two is assumed since they both set the same unusual text (Domine salvum fac regem desiderium cordis ejus), and their settings contain apparently deliberate similarities. Costeley's chansons were by far the most famous part of his output, and they are in the Parisian chanson style of the time, with vivid word painting, along with a tendency to think harmonically rather than polyphonically – as the age of purely polyphonic writing was coming to an end over most of Europe. The subject matter of the chansons is widely varied, as was true for most composers in the genre; some of the chansons are love songs, some are imitations of war or victory odes, and some are humorous or scatological. A peculiarity of Costeley's style – and his notation – is that he specified the accidentals he wanted applied to his music with great care and precision, something which was unusual prior to the middle of the 16th century, but which began to occur thereafter. He was fond of unusual melodic intervals, such as the diminished third, and probably wanted to make sure they were performed correctly. Some of his chansons, for example the earthy Grosse garce noire et tendre, use this interval prominently: in this work he uses it in an imitative passage. In other pieces he uses augmented intervals, including seconds, fourths, fifths, and sixths. Even more unusual than his use of previously prohibited intervals, however, is his pioneering use of microtones. The chanson Seigneur Dieu ta pitié of 1558 made use of justly tuned enharmonic intervals which, if played on a keyboard instrument, would require nineteen keys per octave; Costeley specifies that tuning such an instrument in equal "thirds of a tone" would be necessary to perform his chanson. This amounts to a specification of 19 equal temperament for a keyboard version of this chanson. While he was a member of Jean-Antoine de Baïf's Academie de musique et de poésie, few of his works show the influence of, or intent to contribute to, the newly developed genre of musique mesurée. Only two compositions in the collection entitled Musique, published in 1570, show the metrical freedom which characterizes the style. One instrumental composition by Costeley has survived, and that only in a reconstructed version from a manuscript prepared by a non-musician. It is a short fantasie for organ (Fantasie [pour] orgue ou espinette faicte par monsieur Coteley [musicien] de la Chappelle du Roy), and is considered significant because it is one of the only surviving bits of keyboard music from late 16th-century France, other than pieces transcribed from vocal originals. The repertory of French keyboard players from the time seems to not have been written down, and certainly remained unpublished.

• Airs et chansons au temps du roy Henry. A Sei Voci 1987, digital re-release 2010 • Guillaume Costeley Musicque A Sei Voci Erato Records 1999 • Guillaume Costeley Mignonne Allons Voir Si La Rose: Chansons Spirituelles Et Amoureuses Ludus Modalis, Bruno Boterf Ramée 2013