He translates these characteristics in his oeuvre by using specific processes, which he calls ‘codes’ (2). The different processes carry inside them a tension between stability and movement, which results in two compositional characteristics: panels and filters (3).
The combination of panels and filters leads to a strongly process-based composition. The process itself actually fades to the background; not only for the listener but for the interpreter as well. The music has an organic and gradual character, which is nevertheless routed in a clear process-based method. Filters and panels both induce conservation of the musical material as well as organic growth within the composition, all for the purpose of musical expression.
Donatoni himself used the terms “panel” and “filter”. The former can be found in an interview from 1990 with Enzo Restagno in Autori Vari Donatoni. (Torino: EDT, 1990), p. 44, where Donatoni states: “In 1976 the condition was different... the piece was conceived like a series of panels which interrupt the continuous flow of the orchestra.” The latter is found in the same interview, on p. 31: “You apply... [a] filter or extrapolation to a sequence of pitches...This case involves an autonomous code.” While Donatoni here refers to his earlier period, I am attempting to draw a connection between such older filters and newer ones in his joyous period.
In panels certain musical elements or ideas are conserved over a period of time, which results in a feeling of relative stability. New passages emerge by combining panels in different ways. In these passages the material doesn’t evolve, but is transformed by mutation. These processes of course influence the formal organization of the piece not only on the surface but also on deeper levels, for instance in the shaping of phrases and motives. All possible musical elements – notes, pitch-class sets, interval series, motives, orchestration, etc.- can be part of a panel and in that way subdued to mutation.
Donatoni’s panel approach to form begins with large strands of music, which are developed and realized to their logical conclusion. Sections taken from these strands become formal panels, and are assembled with other panels from other strands according to a formal plan. Each formal panel, taken from a fully realized and developed strand, reveals a moment from that lineage. The different strands interact through changing juxtapositions, thus creating new contexts for the material. Through this technique, the goal of Donatoni’s third point regarding Bartók is achieved: “Juxtaposition of organisms; mutation, not evolution.” Material gains new life through new associations with other materials. The composer uses this technique on many formal levels, from large formal sections on the macro-level, to smaller strands of material within formal sections on the micro-level. He even uses this method to create a small model of the macro-level formal structure by arranging micro-level panels in a similar manner at the climax of the work. These techniques create both cohesion and variety, and contribute to Donatoni’s inventive polyphonic style.
Established musical material in filters can undergo a gradual transformation by applying codes. The filter on the one hand degrades the musical material via gradual diminishing processes. On the other hand, it can also work in a constructive way by gradually building up a new motive. Filters also often conduct the disrupting of continuity; a clear example is a gradual change in the length of musical rests or the addition of rests into the music.
To best achieve a sense of gestural growth, Donatoni often progresses from material in its most filtered state, and gradually proceeds via the filter back to the complete version at the appropriate moment. This is achieved on both a very specific and a more general level, as filters can extract either specific notes from a repeating phrase, or large portions of a recurring texture.