Interactive feedback on extended instruments


  • Carlos Gustavo Román Fundación Universitaria San Martín
  • Timothy Schmele Universitat Pompeu Fabra, Barcelona
  • John O’Connell Universitat Pompeu Fabra, Barcelona



Extended instruments, interaction, network music, feedback.


This project aims at exploring interactivity in networked music by exploiting innovative mapping schemes to extend common musical instruments into acoustic controllers of digital sound. The sensors used were limited to only piezo element contact microphones, as they demonstrate a simple and cheap solution to retrieve an acoustic signal free of most environmental noise and crosstalk. The main idea was to employ the feedback that results from processing a particular system as a control signal, in a way that allows interaction with different musical systems by means of network communication. Another goal was to preserve the traditional techniques in which casual musicians play their instruments, so as to minimize the learning process that the creation of new interfaces require, and maximize the usability of the instruments' extensions. The extension itself is both reactive and transformative. We chose to extend the guitar and a djembe, as an example of a common ensemble of music in casual social contexts.

Author Biographies

  • Carlos Gustavo Román, Fundación Universitaria San Martín

    M. Sc. in Sound and Music Computing, Universitat Pompeu Fabra. Electronic Engineer, Universidad de los Andes. Teacher and researcher for Fundación Universitaria San Martín, Bogotá. He has presented papers at international conferences in New York University, UCLA, Universidade de São Paulo, among others, in topics of music, aesthetics and technology.  He has been a member of the Barcelona Laptop Orchestra.

  • Timothy Schmele, Universitat Pompeu Fabra, Barcelona

    M. Sc. in Sound and Music Computing, Universitat Pompeu Fabra. Composer and researcher in audio technology. He currently works for the Barcelona Media foundation, researching in the 3D audio, sonification and ultrasound fields. He is a member of the Barcelona Laptop Orchestra. His composition "The Common Perkins Scream" recently won the prestigious Luigi Russolo award.

  • John O’Connell, Universitat Pompeu Fabra, Barcelona

    M. Sc. in Sound and Music Computing, Universitat Pompeu Fabra. Programmer and musician. He has worked for Reactable Systems. His current interests are music interaction and mosaicing. He is a member of the Barcelona Laptop Orchestra. Originally from Hibernia, he currently lives in Catalonia.


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Original Research