Unfolding the natural sound object

through electroacoustic composition


We are living in a world which poses many problems to its inhabitants. The industrial revolution at the end of the last century developed new technology put to the service of mankind, but at the same time, this technology contributed to the deterioration of the human condition by degrading the environment with toxic waste, and by generating high levels of noise. This situation hasn’t really changed that much, and quite the contrary, the problem has increased with the rapid growth of urban populations, which are going chaotic and where it is now almost impossible to control degradation of the environment.

The generation of high decibel levels of noise in cities, due to car traffic, construction, street repairs, aircraft, home supplies, etc, has alienated inhabitants from their environment. Composer Barry Truax (1984) has described this situation as "low-fi", meaning that at a certain point, a high level or mixture of noise in cities generates nervous problems and muscular tension, giving way to an attitude of distancing ourselves from the environment by ignoring what is going on around us. In this way, we stop interacting with our environment and stop listening to our surrounding world, considering that everything forms part of that noisy chaos.

As an electroacoustic composer, I have been forced to open my ears to all existing sounds, including those produced by machines [1]. The beauty of these sounds was first noticed at the beginning of this century by futurist Luigi Russolo, who constructed instruments that imitated different noises and who tried to make music with them. [2]. I have myself discovered very pleasant motor sounds such as that of the refrigerator, which produces a changing drone rich in harmonic and inharmonic overtones [3]. Although it is true that certain noises generated by machines can be loud and continuous, and that this steadiness and loudness can be boring and irritating, the main problem is not centered on the existence of an isolated noise like this that we can still perceive, but in the existence of masses of noise, where we can’t differentiate one thing from another. This is what happens most of the time in urban places, and it has become a difficult problem to solve. Nevertheless, I believe that a possible contribution to the solution of the problem could be given by composers, sound engineers and musicians in general. If we can help people to be aware of their daily encounter with noises, maybe then they could reestablish interaction with their soundscape. One way of doing this would be to isolate these sounds from their context by recording them in order to listen to them carefully and learn to find a positive quality in them. This has become possible thanks to the development of electroacoustic technology.

The invention of the tape recorder was of great importance because it was more than a device to record music and events. It was as with the photographic camera, a tool with memory, capable of freezing a portion of reality, and letting us discover the detail of a specific moment. With the camera, photographers started to take images of urban life that generally passed unnoticed to the common citizen. Not having the time and disposition to pay attention to what is going on, the community could nevertheless discover the magic of unimportant moments thanks to the photographer’s work. In the same way, sound engineers started to become interested in recording everyday events that went unnoticed to people. In France, the introduction of the tape recorder started a whole musical current called "musique concrète", based in the recording of all sorts of sounds that were edited to make a composition. Pierre Schaeffer (1966), the leader of this group, believed in "reduced listening" ("l’écoute reduit"), which was listening to a "sound object" out of its context in order to discover its intrinsic physical and musical qualities. Recording and listening through speakers was a good way to abstract a noise from reality, and to detect things in that sound that would be impossible to listen to in real life. Concrete musicians rejected the original meaning of the sound coming from its context, because they thought it was a distracting factor and that it would prevent a musical discourse from being built. Nevertheless, some French musicians coming from this current like Luc Ferrari and others used the metaphoric meaning of environmental recorded sound in their musical work.

The invention of the concept of "sound object" belongs to Pierre Schaeffer. This term is very important because it speaks of the intention to abstract and reveal the qualities of a specific sound by recording and editing it. A sound object can be described as being formed by an attack, a body or steady state, and a decay. New Zealand composer Denis Smalley (1986) has described two main qualities of sound objects which can also serve as a strategy to structure a musical work: gesture and texture. Gesture is concerned with an action directed away from a previous goal or towards a new goal, and is related to the attack and the decay of a sound object. Texture is concerned with the internal behavior on patterning of a sound, with energy directed inwards, re-injected and self-propagating. This term is related to the body or steady state of a sound object. Sound objects are sometimes more gesture or texture-like, and at other times they behave in both ways. The ways to listen to each quality are different. Gesture is more related to the morphology of a sound object, so we listen more to the sound’s external shape and to its rapid movement[4]. On the other hand, texture is related to the spectral content of a sound, and for this reason, we listen to its internal structure. It is important to notice that our way of listening from one quality to the other changes continuously and that sometimes we can’t define where the frontier between them is . Smalley has also used the concepts of gesture and texture to explain structure in electroacoustic music[5], in this way serving both to analyze the micro-structure of a sound object and the macro-structure of a musical work. Thanks to this close relationship between the micro and the macro levels, we could create the whole structure of a musical piece based on the analysis of a sound object.

There have been some electroacoustic composers who have done pieces based on the exploration of the qualities of a natural sound object[6]. Here, the tools used to vary a sound are not the same tools as for written music to vary a rhythmic or melodic motive. Electroacoustic composers have used analog and now digital technology to transform a sound as an artist uses different tools to work with stone in order to create a sculpture. This way of working with sound as an artisan is something quite new. By converting an analog sound into binary numbers (ADC), it can be analyzed with the Fast Fourier Transform (FFT), the resulting analysis altered, and the sound re-synthesized. Through this technique we can now open the sound object and explore both its morphological and spectral qualities, and then be able to manipulate them (Risset, 1991)[7]. In this way, we have discovered the hidden characteristics of sound, and moved a step further from just abstracting it from its context through recording. This is very important to music and to our knowledge of the sound domain.

Acousticians are presently discovering different properties about timbre in sound, but these investigations remain abstract and removed from easy public access. For this reason, I think that the electroacoustic composer should have the social role to reveal the characteristics of the inner world of sound through his/her music. In fact, this has been done in other artistic fields. Visual artists for example have always been concerned about showing their subjective view of the hidden qualities of visual representation by transforming it. If we go back to the beginning of this century, we can see how expressionism tried to express the human psyche by painting deformed personages. In a different way, cubism tried to synthesize different qualities about a subject in the same painting, by cutting, dissecting, and superimposing its elements in a geometric way. These formal painting techniques can be analogous to the different electroacoustic techniques with which we transform natural sound objects. However, working with environmental sounds is like working with real images which are much more compelling than an abstract representation. Even with electroacoustic sound coming from speakers we have the sensation of listening to something real, and for this reason, it is very tempting for composers to take advantage of the metaphoric quality of sound to enrich their musical work.

By processing an environmental sound we affect not only its physical characteristics (timbre), but also its metaphorical meaning. With some of the techniques developed in digital technology, we can apply the spectral envelope of a sound to another by multiplying their signals, producing a hybrid sound as a result. This method is called cross synthesis, and with it we could get for example the sound of a trumpet articulated as a barking dog, or a dog barking with a human voice. This allows us to create a large diversity of metaphoric images starting from the same sound object. There are many other digital techniques to transform a sound object which could change its signification, that I can’t explain here in detail. I would prefer now to explain through my personal experience, how to unfold a natural sound object in a composition, in order to explore its physical and metaphoric qualities.

By means of transforming and working with the same sound object, I arrived at the conclusion that I could open and gradually reveal it in time. The methodology of working with only one sound would define the structure of the whole piece, and would give coherence to the composition in terms of timbre. My first experience in this direction was with my tape piece ATL [8], where I made all the sounds except one, starting from the manipulation of a 7 second sample of a water stream. Other composers have made pieces using water sounds as structural elements, but in this case I tried to do a spectro-morphological research about a particular portion of a water stream sound. In this way, all the micro-characteristics of the original sound object such as its chaotic rhythm and hidden spectral qualities were enlarged. In a way, this works exactly as in fractal theory, where micro structures are self-similar to macro structures. For me, this is a way to contemplate something that in normal conditions would escape us. In this way, the ear acts like a microscope and we have the impression of traveling within the sound and of being covered by it.

The digital techniques which I used to transform the original water sample were mainly traditional EQ filters and digital resonators [9] that emphasized certain frequencies like the fifth and the octave, thus creating different layers of sounds that reproduced the typical "organum" intervals. I also changed the sample rate, creating in this way different self-similar rhythms which were out of phase with each other, but mainly, I was able to come up with new sound textures by changing the sound again and again (by always using resonators, sample rate change, regular filtering, and some stretching). Finally, I created long glissandos by processing the sample with a pitch envelope function, by changing its sample rate and by pasting it over and over.

On the other hand, there is all the metaphoric meaning attached to every sound transformed in the piece, and of the relationship between sounds, because we can’t consider a sound object in a composition as an isolated element. The sound will always say something different depending on the context in which it is found [10]. To make this clear, there is an example at the end of the composition where there are water flows that seem to be swollen from the earth[11]. Following them, a new sound emerges which seems also to be water, but which in fact is one voice speaking, superimposed over and over. This voice becomes like water because of the context it was placed in. A metaphor also rises from the whole structure of the piece. ATL begins with transformed water sounds that have an instrumental quality that reminds us of some eastern instruments such as the drone of the tampura in Indian music or the Buddhist bells from Tibet. These sounds make us think of the ritual or religious events related to the playing of those instruments, and so, the water sounds become part of a ritual that puts us in a state of contemplation. At the end of the piece, the descending waterflows that get stronger and stronger makes us think of falling into something or being swallowed by something. As we relate water to the psyche, this could mean that we are abandoning the conscious realm in order to enter the subconscious, being thus liberated from the rational world by entering into a sort of catharsis.

By unfolding a sound object, I am also trying to show different perspectives of the same thing. Metaphorically, this could be equivalent to a three dimensional sound, being able in this way to perceive its different characteristics. This is like walking around a sculpture in a museum. It changes all the time, but in fact it is always the same sculpture. I used this idea in my composition Frost Clear, which is made from the manipulation of a sample from the motor of a refrigerator. Now, why did I ever think about making music with such a sound?. I used to hate refrigerator sounds because every time I was working near a kitchen, I felt bothered without knowing why. Suddenly, when the refrigerator motor stopped, I realized that my problem had originated from its intermittent sound. It wasn’t until later in Oakland California that I discovered that refrigerators could make beautiful sounds. The sound of my refrigerator’s motor seemed to be like a singing voice because the overtones changed constantly and regularly, and by listening carefully I discovered that the spectral structure of the sound was very rich due to the combination of natural harmonics and inharmonics [12]. There was also a fundamental "hum", as there is a fundamental note for a chord structure. The micro-spectral changes of the refrigerator are generally unnoticed in normal life because in order to listen to them we have to get very near the motor, or amplify it. I tried to use the refrigerator’s motor sound structure in a composition, in order to discover its richness. To accomplish this, I created different sounds by manipulating a refrigerator sample which I recorded with a contact microphone. Every sound was transformed by reverberating a different portion of the original sound’s spectrum, then they were mixed down, having as a result a continuous process where we could listen to the whole spectrum being unfolded through time. As this process is texture-like and has no gesture, we make an effort to distinguish its different components and listen with care to all the micro modulations taking place. As a result, this listening attitude allows us to find the hidden qualities in the motor sound which in real life seems to be just a uniform and static noise. To reinforce the idea of listening to the spectral change of one sound object, I introduced a double bass into the piece that only plays its low open string tuned to the same pitch as the refrigerator "hum". The double bass has instructions to play on different parts of the string, so when the refrigerator overtones are high, the performer plays sul ponticello in order to bring out high overtones as well. In this way there is an analogous continuous transformation of timbre in the double bass sound that follows the process of the refrigerator spectrum.

In the second section of the piece I introduce a new element which is a transformation of the original sound object, but which breaks with its essence. I create discontinuity by fragmenting the different transformed sounds of the beginning, and creating melodies extracted from the frequencies of the original overtones. The shape of the first melodies are constructed with the frequencies of the natural harmonics belonging to the spectrum. Later on, I introduce melodies made out from the inharmonic portion of it, so they become dissonant in relation to the first ones. At the same time, the long sounds from the beginning continue, but new ones appear in the register of the refrigerator’s highest overtones, becoming almost sinusoidal and very piercing to the ear. By fragmenting and using the original sound as musical notes in this section, I render it unreal and artificial. My intention was to create note sequences that resemble the LFO function of a synthesizer, and which make us imagine a machine that is going crazy. By changing the morphology of the original sound I also changed its signification and was able to create a metaphor with which I described a sort of travel into the refrigerator’s entrails, playing in this way with the idea of machines as being dangerous living entities.

The different way of treating the two sections of Frost Clear could be paradoxical, but so it is the existence of technology which can be useful and even beautiful, but also harmful. What could be our conclusions about the effect of refrigerator motor sounds?. Should we make them completely silent, or should we design their motor as to provide a musical noise?. I think that in the future, refrigerators like other noisy pieces of equipment will be silent, but meanwhile, we have to learn to live with them.

Perhaps in the future the sound of old trains and other machines will be a relic in sound archives. These sounds will speak then about history and their richness will be lost, so we have to accept that they have some value. By saying this, it doesn’t mean I am a promoter of machine noises. Futurism and modernism are gone, and today we are desperately looking for solutions to eliminate the high decibel levels produced by man’s inventions in order to be able to tune ourselves with our soundscape. In spite of not finding immediate answers, we have to try to keep our ears open to our environment. For my part, as a composer I will continue to make music out of any interesting sound coming either from natural or from urban contexts, trying in this way to reveal the incredible complexity of the sounds that surround us.


[1] I believe as says John Cage that by opening our ears to all existing sounds in our immediate soundscape we can listen to a new kind of music.

[2] They were called "intona rumuori" (Russolo, 1913).

[3] I discovered some time later that American composer Lamonte Young was a fanatic of motor drones.

[4] We can find the origin of musical gesture in the attack of a sound because it consist of a drastic change in the short period of time called the "transient". This rapid change is perceived as causal because it makes us suppose that there was an action that originated the attack (Smalley, 1986).

[5] In this way there would be gesture-like passages, texture-like passages, passages that go from gesture to texture or vice versa, or multilevel events (Smalley, 1986).

[6] Some of the first electroacoustic pieces made from the exploration of a sound were "Dripsody" (1955) by Hugh LeCaine where he makes a study of a water drop, "Water music" (1960) by Toru Takemitsu, "Concret P-H II" (1958) by Iannis Xenakis, etc.

[7] The Risset article published by IRCAM in 1991 had its origins in the symposium about timbre organized by IRCAM in 1985. It was later published in the revue Analyse musical, no.3, and finally modified for its new version.

[8] ATL means water in nahuatl language which comes from the Aztec culture in the central plain of Mexico.

[9] The software used was Sound tools and Turbosynth from Digidesign.

[10] We have to contemplate the sound object in a determined context because its signification will depend on its relationship with other sound objects and of the relation of those sounds in the piece as a whole (Truax, 1984).

[11] These are the long glissandos.

[12] Inharmonics are the overtones that don’t belong to the natural harmonic spectrum.



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