© Jésus s.Baptista


It has been said several times that, thanks to percussion, Xenakis reintroduced the problem of rhythm that was thought to have disappeared from contemporary music. Architect, engineer and composer, this genius of composition writes music whose complex and harmonious structure contrasts with the explosive energy that comes out of it.

From Xenakis’ close collaboration with the Percussions de Strasbourg came two fundamental works, ten years apart: Persephassa in 1969 and Pléiades in 1979. The first, working on the spacialization of sound, is a sound choreography. The second is one of the composer’s most beautiful pieces. The richness of the timbres, the freedom and coherence of the composition make this work a unique rhythmic adventure.

In 2022, we celebrate the Centenary of the composer as well as the Sixtieth birthday of Les Percussions de Strasbourg.

Iannis XENAKIS – Pléiades (1979) 43′
Iannis XENAKIS – Persephassa (1969) 30′

Iannis XENAKIS – Pléiades (1979)
Commission : Ville de Strasbourg
Dédicatees : Les Percussions de Strasbourg
Re-creation : 24.06.2011 with Ensemble l’Abrupt – Alban Richard, Festival Montpellier Danse, Opéra du Rhin

Pléiades, one of the most beautiful pieces written by Iannis Xenakis. The richness of the timbres, the freedom and the coherence of the composition make this work a unique rhythmic adventure.

The Pleiades usually evoke the cluster of sparkling stars in the right shoulder of the Taurus constellation. In the northern hemisphere, the Pleiades are only visible in winter. A telescope allows us to observe dozens of stars, of which only six are visible to the naked eye, as well as a light milky fog in the same area. According to Greek mythology, this cluster of stars represents the seven sisters or Pleiades, servants of Artemis, Goddess of the Moon. One of the sisters, Electra, is said to have disappeared as a comet, eaten away with grief after the siege and destruction of the city of Troy built by her son Dardanus, victim of the famous Trojan Horse ploy. The whiteness and fog in which the Pleiades appear would be the result of the tears shed by the six sisters abandoned by Electra. Thus, the title Pléiades refers to the six members of the Percussions de Strasbourg. But for Xenakis, the reference to the multiplicity of existence seems more important. 

The very essence of this piece rests on the fact that it is not limited to a simple definition. The instruments used range from keyboards (vibraphone and marimba), to various percussion instruments and the «sixxen» – a percussion instrument specially created for this composition. 
The sixxen is a unique instrument which represents in itself all the idea of Xenakis’ music. It is a huge contribution to modern percussion and to musical creation in the Twentieth Century, because it first places the percussionist into the position of sound designer, producer of his own concept and sound material.

The piece is divided into four parts whose titles refer to the materials used to make the instruments and the sounds they produce: «Mélanges» performed simultaneously by various percussion instruments, then «Métaux», «Claviers» and «Peaux». Listening to the sixxen in «Métaux», one immediately thinks of the gamelan of Indonesia, especially those from Bali, the instruments used in festive music in Japan, the chimes of churches in the Mediterranean basin and the cowbells of the Alps. The richness of timbre of the sixxen is in a way an expression of the different types of life led by man, of which metals are an integral part. 

While giving absolute freedom to the concept of a multiplicity of existence, Xenakis has been able to impose a rule of diversity and unity in the temporal structure of his research towards the creation of a single composition.

Iannis XENAKIS – Persephassa (1969)
Commission : French Ministry of Culture and Persepolis Festival

Dédicatees : Les Percussions de Strasbourg
Creation : 9 september 1969 at the Persepolis Festival (Iran)

Being in the heart of the sound is a dream for man, redefining its space, its distribution is a challenge for composers. In this program, the audience is the central player : the Percussions de Strasbourg musicians are on six stages all around the audience. Closing one’s eyes and getting caught up in the sound, realizing that the entire body becomes a sound sensor. Everything turns into sensations, discoveries, suspensions. An amazing sound world, much wider than what our eyes claim to see…

« Xenakis, the architect of sound, was firmly convinced that there was no justification for sound to come from only one direction. According to him, the usual arrangement of a concert, where the music comes from the front, is only one possibility among others. » Guildo Fischer

Persephassa has established itself as a definitive classic in the percussion repertoire. It was premiered in 1969 in Iran by its dedicatees, the Percussions de Strasbourg.
The title Persephassa refers to the goddess Persephone, or Kore, personification of the telluric forces and transmutations of life. These are linked to the cosmic cycles of living species and to man in particular, the basis being period, iteration, the very essence of number theory and mathematics. This is the underlying reason for the role of percussion, which also symbolized telluric and celestial activities.
At the time of its creation, Xenakis proposed new instruments, the wooden or metal simantras, already used in Orestia and whose original idea can be found in the simandres of the Greek convents, «real nests of an ancestral rhythm not yet destroyed by Radio, Television or invasions».
The 6 percussionists are placed in a ring around the audience, which is thus enclosed in these currents carried by the music. The trajectories cross or evolve according to a sound choreography staged by the composer. Before a game of increasing and decreasing waterfalls, rhythms twirling in space and chaotic clouds of sound unfolds, the sextet’s timpani rolls call Persephassa in an incantation. Through a progressive acceleration, the music will transport the audience in a gigantic whirlwind. If this «tourniquet» evokes the dance of whirling dervishes, Xenakis does not aim at trance: sudden cuts, brief but unpredictably distributed, bring the listener out of his torpor at the end.


25 july 2021Pléiades / Persephassa – Reggia di Caserta, Naples, IT
9 July 2021Pléiades -Plaine des Sports de Hautepierre, Strasbourg, FR
11 september 2021Persephassa – château du Hohlandsbourg, Haut-Rhin, FR
19 march 2021: Pléiades / Persepahassa – Philharmonie de Paris, FR
And many more to be announced…