Composed: 1991-1993
Length: c. 37 minutes
Orchestration: 2 flutes, 2 oboes (2nd = English horn), 2 clarinets, bass clarinet, 2 bassoons, 2 horns, 2 trumpets, 2 trombones, tuba, 3 violins, 2 violas, 2 cellos, and bass, and solo MIDI-fluteFirst Los Angeles Philharmonic performance: May 28, 1996, Pierre Boulez conducting (West Coast premiere)

Pierre Boulez is a ceaseless questioner. His refusal to stop and settle down with a given solution complements a restless perfectionism. This creative doubt might also seem, on the surface, to contradict the supreme confidence Boulez brings to his roles as both composer and conductor. Yet such dichotomies are integral to Boulez’s musical thinking, generating the tension that has made him such a powerful leading force of the postwar avant-garde.

A dialectic tug-of-war runs through Boulez’s work in various guises: the “prepared accident” versus predetermined limits, natural acoustics versus electronic manipulation, and – at the heart of …explosante-fixe… – dynamic flux and movement versus formal logic.

While Boulez’ output as a composer is relatively small, he constructs his works with an intricacy – offering multiple points of entry – that the composer himself has likened to a labyrinth. As a result of his search for an elusive perfection, Boulez keeps revisiting earlier works to draw out new angles, while others generate a constellation of related satellite pieces.

…explosante-fixe… is a characteristic example of a composition which has grown and branched out from its original source. In 1971, shortly after Stravinsky’s death, Boulez prepared a tribute involving a single page of notated music which included several other pages of written instructions for further development. The original line of music gravitated toward the pitch of E-flat (spelled out, per convention, as “Es” = the first letter of Stravinsky’s name). From the start Boulez planned a central role for flute, which would interact with live electronics and a chamber ensemble. However, the technological limitations of the early 1970s proved so frustrating that he put the initial version of …explosante-fixe… aside for the time being.

Aspects of the original material reappeared in other works, such as Rituel in 1975, a kind of requiem for fellow avant-garde composer Bruno Maderna, and, a decade later, Mémoriale, written in memory of flutist Lawrence Beauregard. But with the new possibilities made practical by the composer’s musical research center, IRCAM, Boulez returned to the earlier sketched-out project to elaborate the work into its present 37-minute form for a solo flute interacting with MIDI software in real time, a complement of two other flutes, and a chamber-size acoustic orchestra.

Boulez initially planned a cycle of “transitory” sections (called “Transitoires”) which would number up to VII, each growing in intricacy and involving permutations of the original seven-note cell of the Stravinsky homage (“Originel”). But …explosante-fixe… is devised to work “backwards,” in the sense that it begins with the most complex material and moves ineluctably toward the most primary, so that the Transitoires lead us to the original point of simplicity – an E-flat – from which the music was originally generated. Between each movement are much shorter passages of interlinking electronic music, called “Interstitiels.” To date Boulez has composed the 7th and 5th Transitoires in addition to the basic material, so that …explosante-fixe… plays out in a single uninterrupted sweep of the following: Transitoire VII, Interstitiel, Transitoire V, Insterstitiel, Originel.

The title neatly crystallizes what is at the core of the Boulez aesthetic. It comes from André Breton, the guru of Surrealism, who used the phrase at the end of Nadja, an obsessive prose poem about his obsession with a girl wandering through Paris. Breton compares her beauty to “a train which endlessly roars out of the Gare de Lyon station and which I know shall never leave, and which has not left…Beauty, neither static nor dynamic.” In a subsequent work, L’Amour Fou (Mad Love), Breton again uses the oxymoron “explosive-fixed” as an attribute of the new age of “convulsive Beauty.” As an illustration, he refers to Man Ray’s photograph of a flamenco dancer, her fluid skirts trapped and fixed in motion by the camera.

…explosante-fixe… musically plays this exuberant freedom of the moment off against the complex, predetermined, fixed logic of its form. The kaleidoscopic sensuality of its sound surfaces fascinate and dazzle, regardless of what we know about where we are in the permutation of melodic material or how unfamiliar we are with MIDI technology. So many levels beguile the ear: you can listen to …explosante-fixe…, for example, as a rewrite of the idea of a flute concerto, where the soloist is “shadowed” by two others, their overlayered piping at times suggesting a modernist pastoral.

After the maximum density of the opening, …explosante-fixe… shuffles and regroups patterns from the ensemble to interact with the flute contingent – such as the trio of violins which gain prominence in Transitoire V. Boulez also embeds and integrates the electronics so deftly that these sounds often steal upon us stealthily, until they absorb the acoustic space in shimmering mirages of sound. Conventional gestures such as trills become defamiliarized and weighted with new significance – to be fully revealed in the flickering of the last few minutes, as the flutes return to the original E-flat from which the piece exploded, trembling with a ghostly aura.

— Thomas May writes and lectures about music and the arts.