The piece is based on a Conductus from the Notre Dame school (12th century), titled Procurans odium, meaning “to nurture hatred.” The lower voice of this three-part Conductus is originally a trouvère melody by Blondel de Nesle. The text, which is not used in my composition, originates from the Carmina Burana and may be summarised as follows: to nurture hatred will hardly elevate the wickedness of evildoers; through shared anger the heart becomes entangled. Conversely, if I do not recognise an enemy, this creates the fortunate condition in which lovers find themselves.

In my composition, I have taken striking characteristics of this Conductus as starting points. These include: monophony (reduced entirely to the single-line melody of Blondel de Nesle), which in my work becomes unison. Canon technique emerges from Stimmtausch (voice exchange), meaning that verticality arises from horizontality; canon writing plays a major role throughout the piece. The triple metre is also essential: a continuous sense of three-part rhythmic organisation runs through the entire work.

The composition begins with the Conductus presented very low and in close spacing in the three solo double basses—thus as a quotation. This quoted material undergoes melodic and consequently harmonic transformation (Stimmtausch); the melody of Blondel de Nesle is chromaticised. This transformation is carried out by three solo cellos, while the double basses continue the original Conductus unchanged.

Shortly afterwards, only a melodic remnant—compressed rhythmically—forms the basis of a sound field constructed canonically. Above this sound field is a chorale (woodwinds and brass), vertically derived from the transformed trouvère melody. The whole leads to a climax. The achievement of climax through crescendo becomes a recurring structural principle throughout the work, as does the sound field itself, which represents a highly abstracted form of canon technique.

The unison material that follows the climax in viola and cello also becomes a recurring element. Above this (first instance of) unison material, smaller blocks of sound fields re-enter canonically and repeatedly build towards climaxes.

In short, in Procurans odium the elements—sound field, unison, crescendo—are played against one another, while everything originates from a single source: a trouvère melody, which is finally restored to its original splendour at the end. — Willem Jeths