Uncertainty Theory #4

Pierre Schaeffer, Steve Reich, Charles Dodge, Yoji Yuasa, Olivier Messiaen and Ondes Martenot


Pierre Schaeffer - Etude Aux Chemins De Fer
Steve Reich - Pendulum Music
Charles Dodge - He destroyed her image
Yoji Yuasa - Projection Esemplastic for White Noise


Olivier Messiaen - Fête des belles eaux (1937)


-A glissando in music is an ornamentation, a sound effect consisting of moving quickly from one sound to another, higher and lower, making all the sounds in between be heard, a sweep of possible notes depending on the characteristics of the instrument.

-The color in the music of Olivier Messiaencolor underlies the heart of the music of Messiaen. Messiaen thought that terms such as "tonal", "modal" o "serial" are misleading analytical conveniences. For him there were no modal, tonal or serial compositions, only colored music and uncolored music ara Messiaen, Mozart, Chopin, Wagner, Mussorgsky and Stravinskyall of them wrote strongly colored music.

In some of his scores, Messiaen noted the colors of the music -especially in the Couleurs de la Cité Céleste and in Canyons with towers...- for the purpose of assisting the conductor in interpretation, rather than to specify what colors the listener should experience. The importance of color is linked to the synaesthesia that Messiaen experienced, which made him perceive colors when he listened to or imagined music (although he said he did not visually perceive colors).

George Benjaminwhen asked about the main influence of Messiaen about the composers, he said: "I think of the sheer - the word he liked - color as the most influential...rather more than as a decorative element, [Messiaen showed that color could be fundamental, structural element...the fundamental material of the music itself."


It is an electronic keyboard instrument designed and built by the cellist of the same name. The French Maurice Martenot   (Paris 1898-Clichy 1980) began his musical education at an early age, giving his first cello concert at the age of nine years accompanied by his sister Ginette. Eventually she would become the first soloist on the instrument created by her brother known as the Martenot Waves. Maurice was also passionate about science, an area in which he was completely self-taught, and about teaching. He also wrote books on relaxation and breathing techniques and, together with his older sister Madaleinedeveloped the teaching method Martenotwidely distributed in France.

To understand how the instrument works it is necessary to understand an acoustic phenomenon. The string of an instrument like the piano, when the note A4 is plucked, has a frequency of 440 Hz, that is, it vibrates 440 times per second. Depending on the speed of this vibration, the frequency will be higher or lower. The radio used by Martenot only operated at a very high frequency, emitting an inaudible ultrasonic note to the human ear, of around 40,000 Hz. Therefore, to obtain an audible sound, Martenot used the principle of frequency comparison by interference, a system used by musicians when tuning another instrument, producing beats, by combining two oscillations with two slightly different frequencies to generate a third, whose value is the mathematical difference between the first two frequencies. For example, the note A can be produced by the simultaneous production of two inaudible frequencies of 40,000 and 40,440 Hz. The first frequency is fixed and never changes while the second is variable, modified by the performer playing the instrument, either through a keyboard or by the movement of a wire or tape.

An example of the instrument made with the characteristics of the Martenot Waves, Ondomo designed by the Japanese Naoyuki Omo.