The SIX-XEN by Iannis Xenakis

a Pleiad of ever-expanding sounds




Iannis Xenakis, SIX-XEN, Pléïades, acoustic instrument, percussion


SIX-XEN, the acoustic instrument created by Iannis Xenakis for Pléïades (1978), is representative of the composer's creative process and his interest in percussion. The creator's own descriptions, as well as the connections between the object and his theoretical and practical work, shed light on structuring and fundamental aspects of the conceptual and sonic universe of Xenakis' research. These aspects can be observed through different documents: initial sketches, manuscripts, different editions of Pléïades, letters, personal notes and interviews. As an object created by a composer, the instrument has characteristics that are a direct reflection of its creator's practical and aesthetic approaches. Taking this into consideration, this article addresses the Xenakian percussive instrument with an emphasis on: microtonality, acoustic beat, glissando and variability through non-faithful repetitions. In creating the SIX-XEN, Xenakis entrusted the percussionist community with an enormous responsibility because the research and the construction of prototypes are constant challenges in order to play his piece.


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Author Biography

Ronan Gil de Morais, Federal Institute of Education, Science and Technology of Goiás (IFG), Brazil

He is a percussionist, researcher and professor at the Federal Institute of Education, Science and Technology of Goiás (IFG). He holds a PhD from the University of Basel (Universität Basel, Switzerland) and the Fachhochscule für Musik FHNW in the Musicology program (Kooperationsprojekt Musikwissen). His work was supervised by Prof. Dr. Matthias Schmidt, Prof. Dr. Georges Starobinski and Prof. Christian Dierstein, and he received the citation insigni cum laude. He holds a master's degree in Composition et Interprétation Musicale from the University of Strasbourg (2011), where he presented a dissertation on the repertoire for percussion and mixed electroacoustic music under the guidance of Prof. Dr. Alessandro Arbo and Prof. Emmanuel Séjourné. He studied specialization in percussion keyboards at the Conservatoire de Strasbourg (France) under the guidance of Prof. Séjourné (with a Très bien honorable mention). He holds a Bachelor's degree in Percussion from the Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP-2009), where he played with the Piap Group for four years and won the Excellence in Research Award for his final course work ("Brazilian repertoire for solo vibraphone"). He taught (Chargé de cours/Percussioniste accompagnateur) at the Conservatoire de Strasbourg and taught percussion at the Ecole de Musique de Souffelweyersheim. With the Piap Group he has performed throughout Brazil, in the USA and Canada (during the 2010 North American Tour) and has participated in concerts with the Katia and Marielle Labèque Duo. He has been a member of the most diverse chamber ensembles: AxisModula, Accroche Note, Ensemble Vertebrae, Texture Ensemble da Milano, Babel Trio, DUALpha, DuAnphibios with concerts in France, Italy, Luxembourg and Spain. He has premiered works and worked with Michelle Agnes Magalhães, Charles David Wajnberg, Flo Menezes, Daphné Hejebri, Stefano Gervasoni, Thomas Meadowcroft, Anna Sowa, David Hernandez Ramos, Fernando Iazzetta,Bertrand Gourdy, Zacarias Maia, Gitbi Kwon, Jacopo Costa, Patricia Goberna, Marisa Rezende, José Manoel Gatica, Nicolas Tzortis, Franck Christoph Yeznikian, Vito Zuraj, André Bandeira, among many others. Works by Michelle Agnes Magalhães, Charles David Wajnberg, Daphné Hejebri, Ivan Chiarelli and Roberto Victorio have been dedicated to him. He has recorded CDs with Ensemble Accroche Note, Grupo Piap, Grupo Percussionista de Câmara (GPC) and Euterpe, as well as the CD and DVD of the II Biennial of Contemporary Music in Mato Grosso. He has composed works for percussion ensemble and percussion with electronics (real and deferred time).


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How to Cite

Morais, Ronan Gil de. 2023. “The SIX-XEN by Iannis Xenakis: A Pleiad of Ever-Expanding Sounds”. Per Musi 24 (December):1-31.



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