Mastery of tuning (technique, culture, theoretical approach) gives the performer an additional understanding of a work and its aesthetic context. A veritable reading grid, it establishes the state of mind, the emotional environment of a piece or programme, while revealing relief, nuance, light and shade. It is a sensory guide, an inspiration, for the musician and the listener, opening up a world of hierarchical colours where coherence and contrasts, consonance and harshness invite expressive play. Tuning and organological notions will enable students to become autonomous when it comes to minor operations. By refining their perception of instruments, they will question their technique as well as the ideal sound they have of a school of instrument making or a score.