Schaeffer's Solfège, Percussion, Audio Descriptors: Towards an Interactive Musical System


  • Sérgio Freire Universidade Federal de Minas Gerais
  • José Henrique Padovani Universidade Federal de Minas Gerais
  • Caio Costa Campos Universidade Federal de Minas Gerais


Schaeffer's Solfège, Percussion, Audio Descriptors, Interactive Systems


Pierre Schaeffer's typomorphology (1966) proposes seven criteria of musical perception for the identification and qualification of sound objects, which form the basis of his musical theory. This Solfège fits well into contexts where pitch is not the dominant dimension. Relying on similarities between the practice of reduced listening and the utilization of low-level audio descriptors, we present the first version of a real-time setup in which these descriptors are applied to qualify percussive sounds. The paper describes the tools and strategies used for addressing different criteria: envelope followers with different window sizes and filtering; detection of transients and amplitude modulations; extraction and counting of spectral components; estimation of intrinsic dissonance and spectral distribution; among others. The extracted data is subjected to simple statistical analysis, producing scalar values associated with each segmented object. Finally, we present a variety of examples.

Biografia do Autor

Sérgio Freire, Universidade Federal de Minas Gerais

Sérgio Freire is Associate Professor at the School of Music, Federal University of Minas Gerais (UFMG, Brazil), teaching composition, orchestration and sonology. Since 1998, coordinates the Laboratory for Performance with Interactive Systems (LaPIS). Graduated in Music (composition) at UFMG. Holds a master degree on Sonology (1993), from the Institute of Sonology, The Hague, Holland, and a PhD degree on Communication and Semiotics (2004) from PUC-SP, Brazil. Collaborator researcher at IDMIL (McGill University) from 2017. His main academic and artistic interests are focused on different forms of interaction between the acoustic musical practice and the new technological means. ORCID:

José Henrique Padovani, Universidade Federal de Minas Gerais

José Henrique Padovani is Assistant Professor at the School of Music of the Federal University of Minas Gerais (UFMG), teaching Composition, Computer Music, and Music Theory. Padovani is a member of the Music Graduate Programs at the School of Music at UFMG and the Institute of Arts of the State University of Campinas (UNICAMP). More information at: and ORCID:

Caio Costa Campos, Universidade Federal de Minas Gerais

Caio Campos is informatics technician by CEFET-MG, graduated in Music Teaching and currently graduating in Music Composition at UFMG. Caio Campos has his work and research focused on art and technology, being part of composition, free improvisation and sound art groups and practices, many times in interaction with multiple arts. ORCID:


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Como Citar

Freire, S., Padovani, J. H., & Campos, C. C. (2022). Schaeffer’s Solfège, Percussion, Audio Descriptors: Towards an Interactive Musical System. Revista Vórtex, 10(1). Recuperado de



Dossier "18th Brazilian Symposium on Computer Music"