With great pleasure, also because in a little while I will have to start analyzing the score. First of all, however, I would like to share the presentation of the piece written by Bertrand: it can be found on his website.
http://www.christophebertrand.fr/notices/vertigo.html
Vertigo is a piece for two pianos and large orchestra of 83 musicians. It is a commission from the Festival Musica and the French State.
Vertigo (the title will be explained a little further on) represents my first encounter with what I might call "the large form." In fact, the longest piece I had composed up to that point was my Quartet, which lasts about twenty minutes, but consists of a mosaic of eleven short movements. This time, the stakes were high: writing a twenty-minute piece for two pianos and large orchestra in a single movement (this represented quite a challenge for me, as I am usually fond of relatively short forms). It goes without saying that architectural and especially perceptual concerns played a fundamental role in the composition of this piece.
Evidently, a single movement does not imply a monolithic block in itself; Vertigo is structured into eleven sections proportioned according to the Fibonacci sequence (mirrored): 1 - 2 - 3 - 5 - 8 - 13 - 8 - 5 - 3 - 2 - 1, which implies sections ranging from 26" to 306" (this central section, too long in relation to the others, is consequently subdivided itself according to the proportions 1 - 2 - 3 - 5 - 3 - 2 - 1). All these durations are evidently not perceived as such, but they confer a sense of balance to the whole. My work was based on the notion of perception, starting from the following questions: how to guide the listening? How to give unity to the whole? Various solutions were implemented.
Repetition and variation were inevitable. Three examples. At the beginning of the piece, some instruments of the orchestra (a horn, two clarinets in unison, the violas, etc.) enunciate held, raw, brutal, without vibrato, almost "dirty" ff notes. The two pianos have the unusual role of "active resonators" of the orchestra: very rapid double-second motifs follow the harmonic evolution determined by the successive entries of the orchestral layers: here their role is hidden, totally in the background. These double-seconds will reappear ten minutes later, but more prominently, topped by a single layer: the harmonic scales of the horns. There are two layers, two planes. Finally, towards the conclusion of the piece, the double-seconds become soloistic, their role is primary: it is the third cadence of the piece (only a few discrete natural harmonics from the strings and horns discolor the pianos).
Following the same line of thought, the flutes, oboes, and clarinets play a very high arpeggio, consisting of two diminished sevenths separated by a semitone. This is a clear signal. Such non-octave arrangement will be increasingly present throughout the piece, until it completely invades the harmonic and orchestral space during frenetic tutti.
Finally, a strident cluster of quarter tones in the woodwinds, held in the extreme high register with ffff dynamics, intervenes twice, in identical form: it is a very pregnant signal, immediately recognizable.
To ensure unity to the whole, I also used a certain number of harmonies that circulate throughout the piece: for example, the C-Db-F-G matrix (in all possible transpositions); or the overlapping of two dominant sevenths within the space of an octave (with a very diatonic color, so much so as to seem almost modal). And a certain novelty in my language (as a pendant to this relative diatonicism): cluster writing, in all forms (held, rhythmic, clustered scales, sometimes extreme).
But above all, it is the role of the pianos that predominates in the unity of the piece (it is a concerto, after all!) and explains, in part, the title Vertigo. I have tried to use numerous blurring means: the overlapping of speeds in similar registers, the counterpoint of figures that are very similar harmonically and arithmetically (as is possible on the two keyboards of a harpsichord), and the impurity induced by the microtonal environment (to create the illusion of "non-tempered" pianos). This microtonal environment comes from the natural harmonics of the strings and horns. A almost "alcoholic," blurred, hazy sensation results, like a reflection in slightly moving water.
As Mana's orchestration prefigured, I ask the orchestra for great instrumental virtuosity, always with the purpose of achieving a collective frenzy: like a gigantic ensemble of soloists, a very divided orchestra (43 real parts; at one point 24 violin parts), great speed of execution, extreme tempos (up to"}
a 200 alla croma), tutti orgiastici. Non ho mancato di ricordare una lettera che mi ha scritto Helmut Lachenmann, che mi suggeriva un po’ più di “scrittura criminale”. Spero di esserci arrivato, a volte.
Infine, la seconda spiegazione del titolo è un riferimento allo Scottie di Hitchcock… perché anch’io ho paura del vuoto (del silenzio), e i venti minuti del brano non conoscono alcuna tregua, alcun tempo morto. Nessun silenzio, nessuna lentezza.