Éphémère I & II’ (for tape, or to be played with various instruments) are two previously unpublished masterpieces which represent a very specific moment in the creative life and catalogue of Luc Ferrari. Luc Ferrari was tempted in the mid-1970s by the idea of leaving the final realization of these pieces open to the performer’s intervention (a perspective he decided not to develop in future researches). ‘Exercises d’Improvisation’, a score conceived in 1977 and unreleased for almost 35 years (first recorded this year by the GOL collective with Brunhild Meyer-Ferrari for an LP to be issued on PLANAM), directly comes from the two works presented here. Éphémère I’ (or ‘L’ordinateur ça sert à quoin?’ i.e. ‘What’s the use of computers’) is a 27 minute piece for tape only, created in 1974, conceived as a kind of electronic drone superimposed by fragments of multi-language whispered voices that creates the thrilling effect of a ‘sea-like’ continuum. Éphémère II’ (or ‘Lyon 75’ after the only recorded realization) is a 51 minute tape piece with guitar improvisation. The electronic repetitive structure reminds some of the most radical works of American composer Terry Riley, while the guitar sounds, first resulting as live manipulated pointillistic impulses, develop into a blues sonority superimposing the tape drone and creating a heavy psychedelic atmosphere of the most sublime kind. The end of this long suite lead us back into more abstract and live-electronic sonorities. This very intense work can be placed in a context between scored music and totally improvised music.