Custom spatialisation Pd patch for a large non-conventional area
Author: José Rafael Subía Valdez
Different sound spatialisation tools and methods have flourished and been perfected over the years. Conventional methods are used in typical closed music spaces. Richard Moore's “Space”, Michael Gerzon “Ambisonics” or even traditional “Equal Power Panning” have all been designed for a closed location with a sweet spot where the listener is placed. However what to do when a different area other than ordinary music spaces need spatialisation? This paper describes how the spatialisation patch for Buenos Aires Sonora's “Oi(r) el Ruido” intervention to the (45 x 15 meters) Argentinian Bicentennial Pavilion was created. How was the method picked out and how it was implemented in Pure Data (Pd).
Spatialisation design in modern electroacoustic music is always a necessary matter to be considered by artists. In it's beginnings, electroacoustic artists have investigated and used space in a poetic manner. Pieces like John Chowning's “Turenas” or Karlheinz Stockhousen's “Kontakte” are such examples of music that considered space to have structural importance. Over the last decade, technology has permitted us to move electroacoustic music towards a performatic state and to move it outside the traditional spaces were this music was usually heard. This has obliged sound designers, composers and technicians to think sound design differently in each performance according to where it is going to be executed. To use the original space or to create a new virtual one in each location is a decision based on whether artists want to include the area where the piece is held or do they want to ignore it and create a new virtual one. This decision is purely esthetic but conditions the sound reinforcement design completely.
On January of 2010, the authors services were hired to solve the spatialisation method and programing for the Bicentennial Pavilion intervention. A a 32 loudspeaker arrangement was designed for the structure. Complete liberty was given considering the technical possibilities regarding equipment, time and artistic demands. To do so, the author analyzed the poetic importance of the structures space in the piece and come up with the best solution. After researching and doing some preliminary tests in Pd, it was decided to adapt John Chowning's implementation of Equal Power Panning in “Turenas” method. Also, considering some esthetic spatial factors, reverberation coefficient and doppler effect were included in a unique manner. Finally, custom sound source movement controls were created for a Behringer fader controller, making the GUI (Graphic User Interface), entirely created in Pd, completely flexible.
Pure Data has proven to be a solid and versatile platform to work with. The author's work during this project was centered completely around the technical and esthetic specifications that the project had. Using Pd, allowed the author to freely use the group's equipment and define which was the best spatialisation method for the location and artistic performance. Without Pd, the method of choice would have not been able to be implemented. The spatial goal could not have been achieved regarding that there is not a known tool able to accomplish what the artists had in mind.
4th international Pure Data Convention 2011 Weimar ~ Berlin