Francisco Guerrero Marín

Francisco Guerrero Marín emerged from the cultural desert left by thirty-five years of Franco’s dictatorship and became a model for several generations of composers. He trained contemporary creators who are now firmly woven into the fabric of European music, including Alberto Posadas, Jesús Rueda, and Jesús Torres — younger artists who were drawn to his radical thinking, solid foundations in the field, and his dedication to the work of composition. Guerrero Marín sought his own personal path, resisting fashion and remaining free from the academic constraints of the avant-garde.

An aesthetic inspired by “art-science”

Often described as a “Spanish Xenakis,” Guerrero found in the Greek composer’s music an essential touchstone for creating his own language. The two composers share a statistical treatment of pitch, a dissolution of metric space, a reduction of musical material to basic gestures, a near-obsessive search for formalization, and sometimes violent musical expression.

In the late 1970s, an era of cultural awakening in Spain, Guerrero entered some of Europe’s most important networks for contemporary creation. He was helped both by his early calling (he published his first composition at the age of sixteen) and by the support of established composers such as Luis de Pablo and Tomás Marco, both of whom played major roles in Spanish musical life as catalyzers of avant-garde experimentation between 1950 and 1970. De Pablo especially became a crucial point of reference during Guerrero’s early years as a composer. Yet his most decisive supporter on the international stage was the Belgian musicologist Harry Halbreich, who was among the first to champion his music.

As with Iannis Xenakis, Guerrero drew on the idea of “art-science” proposed by Edgard Varèse. Varèse had captured this idea when he wrote, “I find more musical inspiration in contemplating the stars — especially through a telescope — and in the high poetry of a mathematical proof than in the most sublime recital of human passions.”¹ Guerrero’s own fascination with astronomy and natural phenomena appears in the titles of his works: Rhea, Coma Berenices, Cefeidas, Delta Cephei, Hyades, Sahara, and Dunas. Yet he did not approach science as a source of what Jean-Marc Chouvel called “scientific romanticism.”² Belonging to a younger generation than Varèse, he used mathematics not to kindle poetic inspiration but rather to implement “the procedures and the laws of science in the very act of composing.”³ Similar to many major composers of his era, from Pierre Boulez to György Ligeti and Karlheinz Stockhausen, Guerrero felt a need to ground his music in solid scientific reasoning. Science offered his work an “almost metaphysical aura of infallibility.”⁴ He found in it the foundation on which to build compositions marked by coherence, rigor, and organic growth. “I want to build a musical composition as a tree is built,”⁵ he said, and for this, “the art of sounds, of music, needs this rigorous thinking that is none other than scientific thinking.”⁶

This commitment to scientific rigor did not mean Guerrero rejected expressivity or the communicative capabilities of musical language: “Music,” he stated in a radio interview, “is a reflection of the soul, of the psychic situation or the state of mind of the composer.”⁷ This view is hardly surprising, as Guerrero saw the artist and the human being as profoundly linked. His music places expressive effusion and science on the same footing, producing what Nicolas Darbon described as an “almost savage energy allied with rigor.”⁸

The first phase of formalization: “combinatorics”

Guerrero began by experimenting with techniques drawn from the European avant-garde, including chance procedures, improvisation, gestural writing, and musique concrète. He soon found enumerative combinatorics to be a first-rate tool for formalizing musical structure. This approach had been used by Xenakis in the 1960s and discussed by de Pablo in his 1968 book Approche d’une esthétique de la musique contemporaine. Guerrero applied combinatorics in a theoretical way, using it to regulate his musical materials and to control their evolution over time. In general, he understood musical materials as reducible to three basic categories: “held notes,” “repeated notes,” and “counterpoints.” Thus he could organize relationships among these elements in a refined way. He unified an ensemble of post-serial procedures under the generic name “combinatorics” and initiated a speculative line of inquiry in which, ultimately, intuition and creative freedom take precedence. In his words,

combinatorics is a technique that made it possible to establish links that could run from the first piccolo to the last double bass: strong links throughout the work, not really obvious to the ear or the eye, but important for maintaining structural cohesion. […] At the macroscopic level it was possible to see the whole work from afar and to explain each note precisely, even if the composer could modify something that they didn’t like.⁹

After Actus — in which Guerrero had not yet fully broken away from the influence of Xenakis — Anemos C marked his first successful experiment with this approach. Scored for woodwinds and percussion, it dialogues with the world of Varèse. Its dilated sonorities and stretched tempos also connect with contemporary works such as Pierre Boulez’s Rituel in memoriam Bruno Maderna and Gérard Grisey’s Partiels. In Anemos C, however, the suspended sense of time does not remain undisturbed. Violent eruptions of percussion, mainly drums, interrupt the texture and ultimately come to dominate the work’s trajectory.

Acte préalable, for four percussionists, is an early example of Guerrero’s use of homogenous timbres and monolithic musical forms. A parsimonious deployment of resources gives the piece its strong impact.

In contrast with this concentrated use of timbral and technical tools, the sextets Concierto de camara and Ars Combinatoria (which premiered at IRCAM in 1980), as well as Vâda for instrumental ensemble and two sopranos, showcase the complexity of Guerrero’s writing. The music is kindred to that of Brian Ferneyhough, pushing performers to the limit of what is possible. Guerrero deliberately wrote at the threshold of the unperformable, to give his compositions an almost improvised or highly spontaneous quality. Yet behind this apparent volatility hides a complex and perfectly structured combinatory technique, in which every detail is planned. As he put it, “I prefer to write the ideal version, […] using writing that goes beyond the limits of performance, to give it this flexible character.”¹⁰ This nervous, quicksilver quality recalls an arabesque, or the jagged tiers of the muqarnas that decorate the ceilings of the Alhambra in his native Granada. At the same time, the fractured, roaring sound world that pervades his music evokes the force of flamenco.

Guerrero’s intensity emerges most powerfully in his orchestral writing. Antar Atman (a Sanskrit word that means “interior world”) was his first translation of combinatorics into a piece for large orchestra. In it, he uses timbre to shape an inextricable and complex orchestral mass. String mutes and sul ponticello harmonics alter the color of the ensemble, while the work culminates in an unexpected finale featuring the vibraphones hit with hard mallets. The texture is massed and layered, a dense fabric of sound events: a shifting, seemingly chaotic acoustic space charged with mystery.

Antar Atman also marks an advance in his system of rhythmic combinatorics, where Guerrero works at two levels. The first is that of “salient rhythm,” or rítmica yacente: numerical series that determine note durations. The second is that of metric subdivision, or “subjacent rhythm”: the succession of subdivisions within the parts of a measure.

In Zayin (1983), for string quartet, Guerrero’s combinatory technique reaches an unprecedented level of refinement. Echoing Xenakis’s Ikhoor, composed five years earlier, Zayin uses the three types of material Guerrero favored: held notes, repeated notes, and counterpoint. The title of the piece, “seven” in Hebrew, refers to Guerrero’s favorite number, and his fascination with numerical symbolism. It also corresponds to the number of pieces in the cycle of trios and quartets that Zayin inaugurates, and to the number of possible combinations of three different elements, A, B, and C: A, B, C, AC, AB, BC, and ABC. Although it lasts only four minutes, Zayin displays an expressive and formal density that is characteristic of Guerrero’s work from the mid-1980s onward. It was also a departing point for a structural and aesthetic purification he engaged in until the end of his career.

Ariadna is a kind of companion piece to Zayin. Scored for a twenty-piece string ensemble, it marks another stage in Guerrero’s obsessive exploration of form. As Xenakis often did, Guerrero began by making a simple drawing and using it to build a combinatory structure that avoids superposition of materials. Like Zayin, it reflects his search for simplicity. He also modeled Ariadna on the proportions of Johann Sebastian Bach’s Sixth Brandenburg Concerto. Bach was a key historical reference for Guerrero, who sought continuity, even filiation, with the Baroque composer. This is evident particularly through his choice of materials; the strings, treated as a kind of super-instrument, act as a single unit. The form juxtaposes highly contrasted sound blocks: unisons, for example, against powerful clusters dilated across registers. The piece’s roughness — otherwise unprecedented in Guerrero’s catalogue — brandishes a kind of no-holds-barred “brutalism”¹¹ that erupts in the opening moments, with double stops played fortissimo, sul ponticello, and staccato.

At the threshold of the fractal universe: the “seven-term system”

After the successes of Zayin and Ariadna, which represent the zenith of Guerrero’s combinatory period, he began to seek out new compositional models. This investigation led him into three years of creative silence, but when he emerged, he had developed a new compositional tool drawn from the field of topology.

Guerrero had discovered this branch of mathematics through a student of his, physicist Juan José Morales. Topology allowed him to integrate into formal design the instrumental behaviors he had treated more intuitively in earlier works (for example, the glissandos, tremolos, and harmonics of Zayin). His new paradigm, which he called the “Seven-Term System,”¹² led him to the idea of the fractal. Fractal behavior is that in which the same information is repeated at different scales. Something of this logic is present in the effort to keep a similar underlying structure across different sections, both in musical materials and in how time is organized. Guerrero achieved this sense of topological non-variance by using “axioms that maintain a common element that makes it possible to link all the parts together.”¹³

Composed in 1988, Rhea (named after one of Saturn’s moons) is the first example of Guerrero’s new practice. Written for twelve saxophones, it again reveals his attraction to homogenous instrumental groups; it also explores timbre in a way that gives the music an almost tangible presence. Zayin II, the second of the pieces in the cycle that occupied him for fourteen years, draws on the same topological principles. Nur, for large mixed choir, moves still closer toward fractal simulation, through its subtle formalization of musical materials, each linked to specific designs: the “held notes” are long notes that become interrupted, as well as certain glissandi and trills; the “counterpoints” take the form of oscillating motions, rapid leaps, and related gestures. In Nur, as in the nearly ten other pieces Guerrero composed using voice, his treatment of the voice has almost nothing idiomatic about it. It is rough, and often extremely technically difficult, recalling Xenakis’s Nuits, among others.

Systems of fractal simulation

From the early 1990s onward, inspired by an article by science journalist Martin Gardner¹⁴, Guerrero began an almost compulsive search for ways to use fractal systems to formalize his writing. Working with computer engineer Miguel Ángel Guillén, he developed a series of computer programs that allowed him to realize these ambitions. This was pioneering work in Spain at the time, carried out with extremely limited technological resources.

Guerrero’s earlier works already point toward this new paradigm, at least intuitively. He first used fractal systems deliberately in compositions such as Delta Cephei and the orchestral work Sahara. The latter is doubtless one of the most successful pieces in his catalogue. It uses combinatorics, topology, and fractals to generate a musical form with the proportions of the Mandelbrot set. The pieces that followed — Oleada, Zayin III, Rigel, Zayin IV, Hyades, Zayin V, Sheol, Zayin VI, Zayin VII b, Coma Berenices, and Zayin VII — continue to explore fractal processes and algorithms, albeit without entirely abandoning combinatorics.

Premiered at the twentieth Rencontres Internationales de Metz, Sahara is Guerrero’s most ambitious work in terms of performing forces. The orchestra of eighty-three players is in constant divisi, and certain passages feature as many parts as there are players. Alongside this impressive demonstration of instrumental resources, another striking gesture is the complete absence of woodwinds during the work’s first half, followed by their powerful appearance around the sixth minute. From the strings’ fortissimo unison at the piece’s start, to the maximal register expansion by the end, Sahara releases colossal energy, a crushing impetuousness that is at once categorical and irrefutable.

Fractals first shape the formal level of Guerrero’s music through temporal relationships between sections. They next shape the durations of lower-level materials and treatment of pitch. For the latter, he turned to Brownian curves, which Xenakis had used in the violin piece Mikka and which Guerrero saw as a way to balance randomness and determinism. This approach appears in the Zayin cycle from Zayin III onward.

Guerrero used electronics from the beginning of his career, treating them as a laboratory for realizing his artistic vision. They allowed him to bypass the performer, whom he saw as often an obstacle to the precise realization of his complex ideas. They specifically allowed him to circumvent restrictions relating to rhythm and pitch. However, inconsistent access to technical resources in 1970s Spain forced him away from electronics for nearly two decades.

When he returned to the medium in the 1990s, he composed three electronic pieces: Cefeidas, Rigel, and Hyades. Dedicated to Luigi Nono, with whom Guerrero had a close friendship, Cefeidas is built on a recording of the acoustic piece Rhea, outside fractal models. Rigel modulates pitch using a new algorithm based on the Mandelbrot set (later reused in Sahara). The work’s timbre comes from the digitization of a single second from Cefeidas. Hyades, for its part, is the only work from Guerrero’s late period (that is, the period starting with Anemos C ) to combine electronics and acoustic instruments. Written for bass flute, trombone, and double bass, it also bases its rhythmic treatment on algorithms.

The most radical achievement of Guerrero’s late period, which ended with his sudden death at the age of forty-six, is the string orchestra piece Oleada. Here, he uses algorithms to shape Brownian motion curves algorithmically, transforming them through retrograde, inversion, and related procedures. These techniques, as well as his use of twelve- and twenty-four-note pitch series, run throughout his music, but Oleada pushes them to a new extreme. Scored for fifty instrumental parts, Oleada develops as a perpetual unfurling of sinuous lines and glissandi, forming an almost unfathomable mass of sound. Its “slow but inexorable dynamism of a fluid motion”¹⁵ recalls, in some respects, early works by Krzysztof Penderecki, such as Polymorphia and Fluorescences. As in Sahara, the first fifteen seconds present the curve that will form the basis of what follows. Guerrero subjects the material to constant transformation, expanding, stretching, and concentrating it into new configurations. More than ever before, the sound takes on an organic quality that resists preestablished formal schemes: “The form I am speaking of comprises my work as a living organism. Confronted with it, one can only try to observe the development of an organic process from an external, general perspective.”¹⁶

Coma Berenices, Guerrero’s final orchestral piece, synthesizes the symphonic procedures he had developed throughout his career while also opening the door to new sounds. He pushes his ideas to their limits, bringing to a fitting close an existential and artistic career guided by the pursuit of an inaccessible ideal. Along with the string quartet Zayin II, Coma Berenices represents the ultimate legacy of a composer unlike any other.

*****
Stefano Russomanno describes Guerrero as a “figure of difficult interlocking,”¹⁷ a phrase that captures how resistant both the music and the composer are to any fixed historical or aesthetic frame. That resistance reflects Guerrero’s complex personality, his premature death, his uneasy relationship with the musical world, the immense technical difficulty of his music (which has not diminished with time), and perhaps also the continuing difficulty of accessing his archives. Guerrero remains a kind of “myth” in contemporary music: he remains relatively unknown internationally, and his music is too rarely performed.

Among those who worked with him, almost no one followed in his footsteps. Alberto Posadas retained his teacher’s speculative tendencies, especially in using fractal models and in his ability to open new horizons from Guerrero’s legacy. But other central figures of Spanish music such as Jesús Rueda, David Del Puerto, Jesús Torres, and Cesar Camarero took very different paths. They moved away from fractal mechanisms and statistical treatment of pitch, turning instead to a new tonality. They also declined to adopt the nearly religious significance Guerrero attached to the act of creation.

To conclude, the music of Francisco Guerrero remains, in our eyes, a kind of island in the last decades of the twentieth century. Strange, marginal, and fiercely individual, he built a musical universe with tremendous artistic power. Yet the true significance and influence of that universe still remain to be determined.

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^{1. Quoted in Makis SOLOMOS, “Xenakis-Varèse et la question de la filiation,” in Du son organisé aux arts audio, ed. Timothée Horodyski and Philippe Lalitte, Paris, L’Harmattan, 2007, p. 143. ↩}

^{2. Jean Marc CHOUVEL, “Mathématique et expression: Conversation postume avec Francisco Guerrero,” Papeles del Festival de música española de Cádiz: Homenaje a Francisco Guerrero, no. 3, 2007-2008, pp. 57-61 (here p. 58). ↩}

^{3. Quoted by Nouritza MATOSSIAN speaking of Xenakis, in Iannis Xenakis, Paris: Fayard / Fondation SACEM, 1981, pp. 157-158 ↩}

^{4. CHOUVEL, “Mathématique et expression,” p. 58. ↩}

^{5. Stefano RUSSOMANNO, “Homenaje a Francisco Guerrero,” program note for the performance of Proyecto Gerhard, conducted by Ernest Martínez Izquierdo, Royal Hospital of Granada, 30 June 1998, 47th Festival Internacional de música y danza de Granada. ↩}

^{6. Francisco GUERRERO MARÍN, “Época de ‘neos’: neo-cualquier-cosa…,” Guiarte: Guía mensual de las artes, year II, no. 12, 1994. ↩}

^{7. Julia DEL RÍO, interview for a broadcast of the program Conversaciones on Radio 2, RNE, 1984. ↩}

^{8. Nicolas DARBON, Les musiques du chaos, Paris, L’Harmattan, 2006, p. 153. ↩}

^{9. Francisco GUERRERO MARÍN, Pensamiento musical, lecture given by Francisco Guerrero at La Residencia de Estudiantes, 1994. ↩}

^{10. José Luis GARCÍA DEL BUSTO, interview on the program Diálogos, broadcast by Radio 2, RNE, 1984. ↩}

^{11. MATOSSIAN, Iannis Xenakis, p. 75. ↩}

^{12. It consists of seven elements grouped by three so that between one element and the next there is always something in common; for example, ABC — BDE — DCF — CEG — EFA — GAD. This system is described in Juan José MORALES and Francisco GUERRERO MARÍN, “Música y topología,” Scherzo, no. 43, Madrid, 1990, pp. 102-103. ↩}

^{13. Francisco GUERRERO MARÍN, Pensamiento musical, conférence de Francisco Guerrero à la Residencia de Estudiantes, 1994. ↩}

^{14. Martin GARDNER, “Juegos matemáticos: Música blanda, música parda, curvas fractales y fluctuaciones del tipo 1/f,” Investigación y ciencia no. 21, 1978, Barcelona, pp. 104-113. ↩}

^{15. Stefano RUSSOMANNO, “Materia unica: Suono e presenza nella musica de Francisco Guerrero,” Sonus: Materiali per la musica moderna e contemporánea, no. 19, Milan, 1999, p. 48. ↩}

^{16. Stefano RUSSOMANNO, “Sonido y fractales en la música de Francisco Guerrero,” Doce notas, no. 1, 1997, pp. 28-43. ↩}

^{17. Stefano RUSSOMANNO, program notes for a concert performed on 5 October 2011 at the Juan March Foundation in Madrid. ↩}