About Loops I for flute, I wrote: the sound of the instrument and the techniques of play are less important than the transformation processes implemented. The title of the play (Loops, or loops in French) announces and already designates the writing principle. There is an alliterative side to this title and this spirit will characterize a whole series of pieces based on the same principle. I start small rhythmic patterns that are repeated and change little by little. These are simple formulas which, by successive addition or subtraction, end up creating new loops themselves. In Loops IV, for marimba - as in Loops II and Loops III - I added an extra level to the loop principle. Indeed, the piece is constructed in such a way that the processes of transformation of the cells always return to the motive stated from the beginning. If the music seems to be in perpetual transformation because of the morphing process put in place, the listener will have the impression to go around in circles, since each big process will bring it back to the starting point, like the small local loops. that he will hear throughout the room. Moreover, while remaining above all a very playful piece characterized by rhythmic energy, Loops IV is different from the other parts of the series by the fact that the poetics of the instrument plays a greater role. Thus, the slower sections of the room emphasize the timbre of the marimba and the principle of looping then takes second place to leave room for a form of poetic intensity absent in the other Loops. Loops IV is another stage in my work on percussion, a work initiated in 1992 with The Celebration of the Invisibles, then developed in 1996 in ... in 1999 and 2000 in Tombeau In Memoriam Gérard Grisey and the four variations for percussion and together, then in 2001 in Loops II for vibraphone and finally in 2006 in HORS-JEU for percussion and electronics. Loops IV is dedicated to Jean Geoffroy and Eve Payeur.