The Visualization and Representation of Electroacoustic Music

by David Gray

At first glance, the title of this article would appear to be in conflict with Pierre Schaeffer’s concept of “reduced listening”. However, in view of the practice of composers of electroacoustic music, as revealed to this author in current research, it is relevant to examine and restore the role of visualization in composition within the genre. As a kind of representation, there is an evident need for visualization based on a well founded conceptual framework. It is this author’s belief that this is a significant omission that has arisen from Schaeffer’s early statements. Visualization as an aid to better understanding of compositional processes will be seen to be of value in several areas, namely description, analysis, prescription and archiving.

Discovery and Imagination

Firstly, however, there is an important aspect of the compositional process where visualization can also have some relevance. Imagining and discovering sounds for compositional development are certainly not discrete and independent processes. Whilst both can be described as distinct processes in theory, in practice they usually interact together. Visualization, however, can often assist the act of creating sound purely from aural imagination, and in some instances can be seen to have been essential to the development of particular types of music, or particular approaches to sonic or musical creation. As will be discussed below, this distinction between imagination and discovery relates to what are termed “inner hearing” and “outer hearing”; this point is related to Pierre Schaeffer’s concept of the abstraite and the concrète, and is an essential part of the conceptual framework outlined here. A fundamental position informing this process is that the present lack of a clear and decisive framework for the visual representation of electroacoustic practices hinders the development of aural imagination within the genre. Human imagination thrives on symbols, codes, formalized structures and all the tools of representation that can be called upon. These tools help to enable conceptualization and cognition, and therefore greater understanding.

The suggestion made here therefore is that we need to re-state what has previously been held to be obvious, at least in other fields of practice. Musicians often — but not always — imagine sounds before they are created (or should we more normally say “played”). In some genres, musicians also discover sounds that they had not predicted in detail before they were created. They also combine these processes. Sounds will sometimes be nearly imagined but not in every detail, with final details perhaps being tried out later when improvements are made or discovered. Conversely, a range of outcomes might be imagined, first as part of a process of discovering future musical possibilities. Often, the symbiotic relationship between these approaches is almost instantaneous.

The Emergence of the Imperative of Notation

If musicians do not intend to create or play sounds immediately, then they may need to notate them before they are forgotten. The early history of European notation indicates a response to this need. For example, early European notational systems were at one time based on symbols called “neumes”. The term “neume” is derived from a Greek term meaning “nod” or “sign”. The Latin neuma meant gesture, sign or movement of the hand. These early notational symbols were therefore signs or tokens of particular musical events.

This system seems to have developed with regional variants in different parts of Europe, but all had the same fundamental characteristics. Signs were drawn in the manuscripts above the words of the chant to approximate the relative pitches of the notes. Single notes were drawn either as a dot or a line. If several notes were to be sung to one syllable, they were drawn as a connected group (a neume). A long melisma was written as a number of neumes one after the other.

This notation was perfectly suited to its task, which was to remind singers of the relative pitches of the notes, the shape of each neume, and the number of notes in each neume or melisma of a melody they had learned earlier. It was not designed to inform people of melodies they had never heard before. (Yudkin 1989)

Notation here is being used as an aid to memory. In this case, the music must have been known aurally before. Even so, the aural experience might still have been a matter of that which had only been previously imagined and then memorized. The communication of this music to someone else could not occur merely as a result of using notation such as this. Nevertheless, the notation, although incomplete, had its uses.

In the second half of the thirteenth century, a modification of the modal-rhythmic system enabled individual note shapes to indicate specific values by means of their own graphic representation. No longer was the organum style in fashion. The motet was the principal genre, and the three voices of the motet, with their individual texts and different note lengths, could be kept distinct and precisely coordinated. A notation giving all necessary rhythmic information was now at hand. It was the beginning of a time when the notation of composition was not just a memory aid or an act of compilation and preservation, but the presentation of sufficient information so that musicians who had never heard a piece before could perform it. In that sense it was the beginning of the modern era for Western music notation (Yudkin 1989).

This situation describes notation that is more prescriptive as a set of instructions for the future performance of the music. Yet even so, such notation could not be understood as a complete description of the music, including all of its characteristics. Much would have to be left to the experience, memory, guesswork and prior knowledge of the reader. Of course, in a very real sense the notation of music can never be the actual music itself. There are always aspects of the music that remain unexplained.

All notations are indeterminate in so far as they fail to give a complete specification. Conventional notation is indeterminate in matters of pitch, timbre, method of attack. (Cole 1974, 137)

Neither is a musical score a necessary condition for the occurrence of music. A musical score is merely a tool designed to serve particular functions. Two of these have been mentioned above: as an aid to memory and as a prescriptive set of instructions for performance. Broadly, we can categorize scores as being prescriptive or descriptive. Prescriptive scores include performance, realization and diffusion scores of all kinds. Descriptive scores include any representation of how particular music has sounded or might sound in the future, and may go as far as to include analysis scores that help to identify trends, structures and characteristics of particular music. Descriptive scores may also exist as a way of preserving or archiving particular music. Sometimes scores are of both types simultaneously. Scores are always visual representations of music, and as such they are records of musical intentions that have either taken place or are to take place in the future. It can be said therefore that notation can help to clarify and identify that which has been imagined, and describe or record that which has been established or discovered. An example of this is the facsimile of a folk song transcription by Bartók (Fig. 1). Whilst this is clearly based on conventional Western notation, there are additional annotations that clarify tonal inflexions, improvisatory rhythmic elements and transcriptions of moments of de-tuning.

The Notation of Timbre

Whilst it has been possible to devise, evolve and adapt useful systems of notation that deal with pitch in music, the same cannot readily be said of timbre. Part of the reason for this may be fundamental misconceptions as to the nature of timbre. In the first place timbre is commonly regarded as a more secondary or even decorative characteristic of musical sound, often very much less important than pitch (cf. Boulez’ On Music Today). This conflicts, however, with the nature of sound waves themselves. Complex waveforms only develop perceivable pitch characteristics when they are more or less periodic. Sounds with significant pitch characteristics are quite a rarity as compared to the totality of sounds in general. Pitch should therefore be considered to be a subset of timbre. A proper understanding of the relationship between timbre and pitch promotes a much better understanding of the nature of music itself, and especially one that more easily embraces all of the many types of music that have so far existed in the world.

The fundamental question, therefore, is whether it is possible to write down something meaningful, understandable and useful about sound objects that are predominantly timbral, in order to aid the realization of these objects from one’s imagination, particularly when making sound objects electronically. The problems to be overcome concern aspects such as:

• The nature of sound itself;
• The characteristics of timbre;
• The architecture of particular machines;
• The predictability of machines;
• The characteristics of various types of notation;
• The relationship between imagination and discovery in musical composition;
• The invention, and the perception and notation of time in music.

It is possible that producing sound objects from written notation, or visualization of some kind, will produce more considered results that more specifically match compositional intentions. Far more detail about each sound object can be considered as part of the visualization process. Sounds are therefore reflected upon and refined in imaginative terms. This has a parallel in compositions where pitch is predominant. Once they have been visualized, relationships between different objects and their various characteristics are also easier to notice and to formalize than when they remain in the abstract domain. For example, the sample roots or envelopes of different objects might relate to each other; there might be similarities or there might be contrasts. Analysis and synthesis can be more considered in this visual environment. Again, this is what happens thematically where pitch is predominant. To some extent this is fundamental to musical argument and development of almost any kind. There is therefore some degree of commonality about the ways in which musical processes, and argument are developed, no matter what musical parameters are involved.

One of the concerns at present is to consider the evolution of electroacoustic music as one of a number of contemporary musical genres, and that its evolution runs sometimes in parallel with and sometimes in opposition to these other genres. The sounds, structures and syntax of electroacoustic music are rich, diverse and may be very different when compared to other genres. As already mentioned, these differences stem from its origins in the history of recording and broadcasting, the fact that instrumental performance is very often absent from its live presentation, and that often it is the composer who produces the final product.

The Taxonomical Structure

A major part of the research that has informed the present discussion was the study of current practices of composers in the various electroacoustic genres regarding visualization and representation, as part of the compositional process and compositional understanding. This study was partly carried out by means of interviews and a questionnaire. Quite early on, it was realized that responses to this process would bring forth both similarities and differences in the approach to representation, including more explicit visualization. Over the course of the study, it was possible to classify responses according to the way in which specific compositional, analytical, preservation and performance needs are met by composers employing some form of visualization at some point during the creation of a new work. As a result of this, a taxonomical structure that summarizes many of these practices could be devised. This structure is in itself a representation of the significant processes, and how they relate to each other. Moreover, it is effective in identifying the extent to which particular approaches work towards achieving aims either stated by the composer during the compositional process or perceived by this author following analysis of the composer’s completed work, with respect to enhanced compositional understanding.

Broadly, the structure separates the why, what and the how of visualization. Embedded in the conceptual framework of why will be the notions of who for and for what purpose. This structure is not a definitive solution, but its formulation points to the kind of processes that the visualization of electroacoustic music might entail (Fig. 3). The evidence from the questionnaires indicates that most composers do use visualization of some kind either within the compositional process or subsequent to its completion, although some do not. The how also refers to whether visualization is executed by hand or by machine, the latter normally using some kind of software.

There is, of course, a relationship between why and what, because the needs and reason for visualization will determine the kind of visualization that is developed. A specific example of this is the Acousmographe software developed by GRM, and the later EAnalysis. Pierre Couprie has indicated that the why that led to the software’s development is the need for analysis (Couprie 2007). On the other hand, archiving, or preservation, carries with it a need for permanence, or at least a need for retrieval of information at a later date within or beyond the framework of the compositional process. “Preservation” is probably a more accurate term in this case. The need to preserve enough information about a composition to enable it to be re-created later suggests a level of permanence that is as yet not easily achievable in electroacoustic genres, or indeed for any music that is predominantly timbre-oriented and completed in the studio. Trevor Wishart is a rare example of a composer who nevertheless has expressed a need for this level of permanence. It may be that the difficulties of archiving timbral events have deterred composers from thinking that this can be usefully achieved.

Sometimes annotations of some kind are needed for performance. Particularly common, for example, are diffusion scores, but also some kind of visualization might be needed if live interaction or instrumental performance is involved. The extent to which these needs are answered may determine whether a visualization is prescriptive or descriptive.

Inner and outer hearing were referred to earlier. Here “inner hearing” refers to that part of the compositional processes where sound exists in the imagination before the sound comes to be made, for example in the studio. “Outer hearing” refers to that part of compositional processes where sound has already been composed, made or discovered in the studio. For reference to be made at a later date to sound created as yet only in the imagination, visualization is essential either in the form of an archive — i.e. as an aide-memoire, or for future analysis — or indeed for performance, in the sense of “How is this sound to be made and what might its relationship to other sounds in the piece be?” This is an essential part of the conceptual framework of the present discussion around visualization and electroacoustic music. It also makes clear how visualization can play an essential role in the on-going compositional process. Alongside this point, prescriptive representations involve annotations that specifically refer to how a sound is to be made. This can be contrasted with representations that involve annotations that describe how a sound was made. Of course, some representations may in practice fulfil both of these functions. These points are also important because they enable comparisons to be made with visualizations of other types of music, including the long-established traditional notation of Western Classical music.

In some cases, visualizations produced for the purpose of analysis or archive are used for broader tasks within musicology and also pedagogy. Robert Normandeau’s encouragement of students to produce visualizations of their compositions is an example of pedagogical practice as revealed to this author in an interview in March 2007.

What kind of visualization of course arises from the why issues mentioned above. Broadly, there needs to be a distinction made between visualizations produced by hand and those produced by machine, for example in the form of software. Apart from obvious examples such as Acousmographe or EAnalysis, it is to be noted that most commercial sequencing and sampling software involve some kind of visualization. ProTools, for example, offers an “arrange” window where sound objects, MIDI sequences and audio tracks are placed in position, and can to some extent be edited as a result of what can be seen in the window and in the subsequent windows that follow from this. This can be contrasted with common technologies from the late 1960s to the early 1980s, where a graphical interface or GUI such as offered by ProTools and others was sorely missed and made editing sounds extremely difficult.

Text, Graphics, Numbers

A visual representation for whatever reason may involve any of text, graphics and numbers. This is shared in common with other systems and genres such as Western Classical music and indeed its derivatives such as current adaptions for annotating pop, rock, world music, and jazz and fusion. A good contemporary example of this is Berio’s score for Sequenza III for unaccompanied voice (Fig. 2).

In this case we can see text in the form of notes on the score and interpretive instructions both for the score and the music as well as graphics in the form of gestural and other interpretive symbols, sometimes involving the invention of new symbols, or new symbols adapted from more traditional notation; and in a few cases numbers to indicate proportions, perhaps as related to durations.

The outline of a taxonomical structure that includes the use of text, graphics and numbers is an attempt to summarize visualization activity as it might be applied to the composition of electroacoustic music. It is informed by what composers have indicated to me that they do, as well as by what written studies have shown to be the issues. It also indicates why visualization, as developed in software, is formulated to achieve particular results: results that are frequently taken for granted, sometimes almost without question. This taxonomy is both logical and justifiable, and consistent with observed practice both in visualization and compositional process. It is also consistent with compositional process in other musical genres and other types of music. Like other kinds of music, electroacoustic music has particular styles, resources, parametrical focus and presentation of performance. It is, however, music and is understood and responded to as such. I would argue that much of what Trevor Wishart for example terms “sonic art” is music, and thus there need be no distinction between the two.

The diagramme shown in Figure 3 emphasizes the significance of visualization to the compositional process in promoting compositional understanding and reflection, particularly as regards to work-in-progress. It also emphasizes the importance and significance of visualization to a composer’s analytical needs, the need for preservation or archive, and any performance needs that a particular composition may require. These issues are highlighted in order to clarify their importance. This author believes that the research has revealed and clarified the significance of these issues within the compositional process, not only of electroacoustic music, but of music generally. The possible use of text, graphics and numbers in a visualization is made clear as part of the diagramme.

The Musical Archive

The term “archive” is best understood in the present context as one possible form of preservation. Composers use visualization and representation to preserve something about their music as a part of the compositional process, especially to refer back to later as that process develops. This can include decisions, evolution of sounds and the processes involved and relationships between different materials or between aspects of a single material. This preservation may be for future reference as an on-going part of the compositional act, or some kind of permanent record of aspects of the work when completed.

Musically, the archive was something of an imperative before recording. This may account in part for the particular relationship traditional notation has with much Western Classical music, which relies for its production on the performer as an intermediary. Electroacoustic music is a genre made possible by and emerging from recording. However, in electroacoustic music the archive is still thought to be necessary by some composers and practitioners, partly because preservation of digital data can be problematic in that it degrades over time, and then requires re-copying and, more importantly, verification. Additionally, some kind of preservation may be necessary as a reference point when work-in-progress is returned to. The separation from the pragmatic necessity of the hard copy required by much earlier music, not least because of its performance, has caused the electroacoustic genre to free itself from many of the representational constraints demanded by hard-copy archiving. It has to be remembered that when live performance is involved with electronics, then usually some kind of representation becomes necessary. The extreme position, as stated by Simon Emmerson at the 2007 EMS Conference at De Montfort University, is to say that the problem of preservation, of electroacoustic and other forms of new music is “becoming a redundant and obsolete idea.” Indeed, it was suggested at the time that composers who seek final preservation of their work, may perhaps cease to exist in the future and become somewhat “a thing of the past” (Emmerson 2007b). Certainly we can say, at the moment, that the development of recording has at the very least altered the way in which composers and other practitioners put preservation into practice. Later, in the course of subsequent meetings with this author, Simon Emmerson refined these assertions to suggest that “preservation will increasingly happen automatically” (Emmerson 2007c).

The need to preserve or create an archive has been stated by, for example, Trevor Wishart in an interview given to this author in July 2009. This might be seen in contrast to his ideas expressed in On Sonic Art. Archiving was touched upon and expressed as a need by Michael Young and Barry Truax at the 2007 EMS Conference. Some of the composers who participated in the earlier mentioned questionnaire have also indicated in their responses that they believe the representation of music as data is a way of working towards the preservation of an archive of such music.

Timbral Composition and Composing Timbre

It is necessary at this point to draw a distinction between timbral composition and composing timbre. It seems to this author that timbral composition is the composition of musical sound through the manipulation of timbral elements for musically æsthetic or musically discursive reasons. Composing timbre, on the other hand, involves the actual imagining of timbre to some extent, for musically æsthetic or musically discursive reasons. In practice these two approaches may well be indistinct at times, in the way that they might occur in particular music. Timbral composition implies making sounds that are predominantly timbral. Composing timbre means to imagine sounds that are yet to be made, and as yet only exist in the imagination. Visualization may well have a role to play here, in order that “imagined objects or sonic events” can be preserved in some way pending their actual production. Essentially, composing timbre involves the same kinds of musical thinking as does composing pitch and/or duration, particularly as regards thinking of the sound imaginatively. It is likely to involve elements of prescription, description, preservation and analysis, in order to manipulate organizational structures so as to carry out some kind of musical argument, all of which might be assisted by some kind of visualization. As far as the resulting timbre is concerned, the structures will have different qualities to those of other musical parameters, but the same kinds of processes occur. These can be summarized as:

1. Establishment of identities (motifs, objects, events);
2. Comparisons as to similarity or dissimilarity of identities;
3. Establishment of relationships between identities;
4. Analysis of identities sometimes to form new ones;
5. Synthesis of identities sometimes to form new ones;
6. Transformation of identities;
7. More general evolution of new identities having a relationship with existing ones.

The musical parameters pitch, duration, timbre and dynamics have all had their possibilities extended or adapted by electronic technology. However, the sonic possibilities that electronics have made available have made necessary a reappraisal of the role of timbre and its notation in music, and even of what timbre as a phenomenon actually is. Perhaps this is not surprising, because all sound waves are timbral; only those sound waves that become periodic can begin to offer the perception of pitch. It is also true to say, however, that this is not commonly accepted. Certainly, given the development of musical history and how it has traditionally been written and presented, we could be forgiven for thinking that pitch and duration predominate over timbre. However, there can be no pitch without timbre, and for timbre and sounds to exist at all, they have to take place over time, or have duration. It is necessary, in searching for the truth to the structure of musical hierarchies (namely pitch as a subset of timbre), to view all of the contributory factors that have made music possible. Musicians have always concerned themselves with things like the manufacture and design of suitable instruments, and the evolution of sonic structures. These types of decision have normally been made before music is composed or played. Ultimately, therefore, music is a sonic art, and it derives its meaning from sounds made or presented over time. The following points may help to summarize this situation:

• Timbre is important enough to predominate in some compositional work;
• Timbre is multi-dimensional and therefore difficult to visualize;
• Pitch is a subset of timbre in that only certain sounds possess pitch characteristics;
• The predominance of pitch may be a result of its comparative ease of notation;
• Electronic technology has increased the potential of timbre as a musical parameter to affect or even dominate compositional development;
• Electronic and acoustic instruments and sounds have the same potential relationship with compositional and timbral development.

Conclusions

It is clear from the investigations conducted in the PhD research that gave rise to the present text that in spite of the æsthetic philosophy of Schaeffer and others, visualization has indeed been continually used as part of the composition of electroacoustic music. However, and this is known at least anecdotally, we are a long way from being able to easily use visualization an archive that is capable of preserving the means to re-create compositions with anywhere nearly enough prescriptive detail. Yet this would seem to be desirable, given the insecurity of the long-term preservation of data. In the case of electroacoustic music, many will think that this is because electroacoustic music is usually predominantly timbral. The multi-dimensional nature of timbre makes it extremely difficult to notate these complex events, which may be continually changing over time. A visual analogue of such an audible passage of time seems so complex as to be impractical.

In conventional Western Classical music, an archive is possible because procedures concerning performance are fairly well agreed upon, and can be learnt. The use of notation also assumes that the act of performance is ultimately necessary to mediate the creation of the music represented in the notation, or score. This is possible because the notation of pitch and duration are to some extent agreed upon and understood beforehand, within the particular musical style in question. Timbre and dynamics are determined by the instruments selected for performance, and by the ensembles created with those instruments. The re-creation is therefore achieved by performers following these specific annotations. This has, of course, become a complex fine art in itself, and the act of re-creation includes the arts of orchestration and conducting, and interpretation in general.

In the case of electroacoustic music, it might be possible to leave sufficiently detailed visualizations to lead the way to such a re-creation, providing that the conceptual framework on which they are based could be sufficiently clear, rigorous and, most importantly, universally agreed upon. But at the moment it would be a potentially time-consuming and lengthy process. It would also require a measure of agreement as to the meaning of various symbols. And the desire to reach this agreement might well tend to constrain the nature of the resultant sounds.

The other activities referred to here, such as description, analysis, understanding and reflection, can clearly be assisted and enhanced by effective and suitably designed visualization. Some kind of visualization of an as-yet-only-imagined timbre is clearly possible, and in fact regularly takes place as part of the compositional act. Therefore, it is fundamental to the compositional act that auditory structures ultimately need a representation that allows them to be grasped and understood in their entirety. We need to see the musical meaning of these structures as a Gestalt, precisely because in their real essence they evolve over time. The passage of time over a work needs at some point to be grasped as a single entity, if understanding of the work is to be totally complete. It is as if in music it is the passage of time itself that demands the visualization, in order to encapsulate the whole thing as a complete entity. Visualization is likely to be an essential precursor to the final auditory experience, and that experience in all its complexity only takes place over time. Auditory experience is elusive because its frame of reference or inhabited dimension is time. And at the moment, it is only the perception and cognition of space that allows us to see, represent, and fully understand the many aspects of time.

Visualization and representation of electroacoustic music would be a fundamental omission of the genre, if it had ever really taken place. In spite of the urgings of Pierre Schaeffer, this has never happened. Given that visualization has always taken place, a clearer recognition of this by electroacoustic composers would allow a more effective conceptual framework to develop, which in turn would allow a better understanding of the role of visualization as a valuable aid to the composition of electroacoustic music. It might also allow the development of better tools to achieve this.

To put these points more exactly, visualization of timbre and therefore electroacoustic music does not presently have a shared network of symbols, or a shared agreement as to how such visualization should take place. In any case, timbre has notorious difficulties as regards visualization because, as has been stated, it is multi-dimensional in character. Whilst this is not insurmountable as regards description, analysis, some archives, aide-memoires, or simply reflection, it is not currently possible to leave a sufficiently detailed, prescriptive and meaningful archive that would be capable of allowing sounds to be re-created in the future in all circumstances. As soon as re-creation is required, the type of sounds become constrained by the technology imposed by the visualization, even if that technology is simply pencil and paper, that perhaps even offer technological instructions.

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