1. The Beginning of the Journey

Just as the question of instrumental synthesis has over time become a technical matter for many generations who mastered composition with complex sounds, the question of musical time theorised and then put into practice by Grisey also represented an innovative aspect in the 1970s [1]. The need to visually represent the concept of duration that is divorced from pulsed time led Grisey to use a system of continuous lines that extend beyond the bar (when this is present and there is not instead a simple temporal field indicated in seconds). The internal life of a single sound is controlled by meticulous dynamic indications. Both aspects require careful study, especially when the various instrumental entries mimic and magnify the transient attack of a sound model (such as the beginning of Partiels). As this is a delicate aspect in terms of realising the score, Valade warns the orchestra: “Grisey uses proportional time notation. There is a thick line for the bar line, and thin lines for the beats. The notes should be performed depending on their position within the beat (on the beat when on the line - in fact just after the line for reading clarity -, on the half beat when centred between two beat lines, etc.). The purpose of this notation is to consider time as being continuous with no real pulsation. Therefore, there is no emphasis whatsoever on the beats. When a specific rhythmical event occurs, it can also be written with additional conventional rhythms in order to enhance accuracy when necessary.” [2] This warning is then followed by four pages of “Beating indications” where the conductor has detailed all special beatings, piece by piece.

The plurality of notational modes of rhythms and durations within the various movements of Les Espaces Acoustiques is the consequence of adopting the metaphor of sound as a living entity as a model for the formal (and harmonic) articulation of spectral music. As Grisey himself expressed it in his first theoretical text “Devenir du son”, “The different processes of transformation of one sound into another or of a set of sounds into another set constitute the very basis of my compositions, the first idea, the gene of every composition. The material is derived from the sound becoming, from the macrostructure and not the other way round. [...] It is the process that is primordial, [...].” [3] The very notion of process which deeply informs the spectral technique [4] requires a meticulous construction and control of the transformation of sound states according to Stockhausen’s concept of degree of change (Verränderungsgrad), which Grisey has deeply internalised in his compositions. It is thanks to the control of the difference between points in a process that it can be oriented and carried out at different speeds and degrees of linearity, as Grisey has well illustrated in the tables shown in Tempus ex machina [5]. This way of conceiving the evolution of musical discourse is reflected in the notation; examples such as the one illustrated in Figure 3 are therefore very frequent. Here a global process of increasing the inharmonicity up to the maximum of density at figure 14 is articulated as a dynamic-discontinuous process with irregular alternation of durations for harmonic spectrum (8 7 6 5 3 3 3 10 4 22 6 semiquavers) and the complex inharmonic spectrum (12 18 14 8 8 3 14 6 23 23 semiquavers) [6]. From the point of view of beating time, a series of precautions shared between the conductor and the ensemble are necessary in order to correctly conduct the process of transformation as a consequence of the idea of the irregular increasing of inharmonicity. In Figure 3, an analysis of possible internal articulation for beating is given, including indications that are useful to the conductor organising the gestures in order to control the irregular attacks of every aggregate. However, the experience of conducting this passage led Valade to an effective simplification of the gesture, which is thus reduced to indicating only the beat of each aggregate (as can be seen from the instructions sent to the orchestra “Fig.13: every bar in 1 ! (just the down beat)”) [7].

As his spectral compositional technique evolved, Grisey gradually introduced the simultaneous presence of multiple transformation processes that are manifested on the one hand by overlapping harmonic fields, but also by multiple temporal layers that flow independently but which are nevertheless correlated. Examples of this multiplication and expansion of acoustic space can be found especially from Modulations onwards. However, from the point of view of conducting, many pages of Transitoires are particularly interesting. Figure 4 shows the first page of figure 12, the part where Modulations, if followed by Transitoires, connects with the latter. Up to figure 17, where the new Transitioires material starts, the transition is articulated as a long and gradual slowdown of the energy accumulated by the Modulations E part, constructed on the acoustical model of reversed sound by a cymbal that completes its path in the bar before figure 12 [8]. The transition from this great explosion to the repeated gesture in the double basses – the figure that is taken up by Partiels and expanded as a distinctive element of Transitoires –, is articulated on several levels: sustained sounds in the accordion and Hammond organ are enhanced by the electric guitar played with a bow; the glissando of harmonics in the strings blends with the descending figures in the woodwind, the heart of the long rallentando process that is underway. In fact, Grisey himself indicates that the attacks for, respectively, Ob. 1, Cl. 2, Cl. 3, Fl. 2, Fl. 1 and again Ob. 1, Cl. 2, Cl. 1, Fl. 2 and Fl. 1 are to be given special emphasis. Thus, there are two levels on play: first, the regular three-crotchet beat that regulates the macro-duration and second, the individual gestures that on a local level, thanks to the lengthening of the last note of the descending figure, realise the slowing down of the global activity. The whole process is also supported by the rallentando written in the percussion parts. The annotations on the score belong to different types of signs. Blue is used to indicate the general diminuendo and rallentando. The red circled triangles indicate the gesture that is more demanding in terms of clarity of conducting (here they are in means of orientation to where everyone doing the rallentando of the groups of notes should be exactly), whereas the yellow colour highlights the percussionist's particular gesture with the cymbals, and finally, Grisey's instructions are transcribed in blue pencil [9].

A last example of the complexity of rhythmic and durational notation is shown in Figure 5. Here the process of the thirteen repetitions (figures 18-40) of the motif in the double bass is superimposed on two other instrumental levels with different factors of time extension and various combination in terms of orchestration. The simulation of the attack transient requires meticulous articulation of the entries, requiring Grisey to calculate a particular duration for each bar, and requiring the conductor to find specific solutions for these important changes. As can be seen in Figure 5, the solution Valade adopts consists of changing the metronome at the narrowest spaces in the measure that correspond to shorter durations [10]. This page is full of other indications concerning intonation (e.g. for the cl. and B.Cl. part), timbre (horns and the presence of the wind machine) and dynamics. In fact, it is data that becomes relevant, as will be seen in the next section, at the moment when one starts to construct the sound with the ensemble.