Heptagramme (2008) is structured in four parts. The first movement, of a rhythmic nature, is written in “repetitive evolutionary”, a technique dear to the composer and which consists of progressively constructing various melodic-rhythmic cells, repeating them a certain number of times but varying one or more elements (timbre, instrumentation, register, dynamics, etc.) as much as possible within the framework of these repetitions.
Moreover, these cells may follow one another melodically so as to form themes of variable length, or they may superimpose themselves contrapuntally so as to create complex polyphonies/polyrythmies. Surprising modulations also bring frequent colour changes. Very lyrical and expressive, the second movement, in F sharp Phrygian, uses three themes written in invertible counterpoint; these pass from one instrument to another, creating an increasing tension that leads to the central climax marked by a sudden modulation to the upper minor third (the Phrygian). The general dynamics remain “strong” until the end, while the initial mode is used to conclude. The third movement, in D oriental, is essentially exclusively contrapuntal: it opens with a long duet without piano in which the phrasings and the incessant changes of measure create a sensation of polymetry, even if for ease of execution all the parts are written in identical measures. The two instruments are joined at the end by the piano in order to flesh out the polyphony. The fourth and last movement is based on an ostinato that runs through the whole piece, passing from one instrument to the other but essentially played by the piano.
An easily recognizable first theme is grafted on top of it, developed in various ways until a second, more melodic theme appears. Several modulations punctuate the discourse and the movement ends in a virtuoso and brilliant way by exploiting fragments of the first theme.