In this article, the author presents several analytic approaches to Horacio Vaggione's piano and tape piece Till (1991). After an initial consideration of the context of composition, the analysis proceeds in three parts. 1) The tape is investigated between the meso- (middle) and the microscopic temporal levels and a typology of the sound objects is established. 2) The piano's complementary temporal field is examined and a corresponding typology of the musical figures constructed. 3) The modalities of interaction between the tape and the piano, their complementary temporal levels and their ‘common vectorisation' are considered.