Immediately after Canti per 13, Nono wrote Incontri per 24 Strumenti, a work that represents the turning point in his approach to serial thought. For the first time, the subtle dialectic of construction and expression that would characterize Nono's mature style unfolds here. Incontri is divided into two halves, the second of which is the exact retrograde of the first. Since the series of pitches (B flat, C, C sharp, F sharp, E, G, D, E flat, F, A, B, A flat) is constantly proposed in the fundamental position, it is the remaining parameters (duration, timbre, intensity, but also registers and density) that assume the role of bearers of the musical meaning.