# Realizations & Expansions Performance Cases of an Open Work using Artificial Intelligence Generative Tools

Mikhail Malt, Benny Sluchin

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Mikhail Malt, Benny Sluchin. Realizations & Expansions Performance Cases of an Open Work using Artificial Intelligence Generative Tools. ICMC 2025, Northeastern University, New England Conservatory, Berklee College of Music, Boston Conservatory at Berklee et Emerson College, Jun 2025, Boston (MA), United States. hal-05070597

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# Realizations & Expansions
## Performance Cases of an Open Work using Artificial Intelligence Generative Tools

Benny Sluchin

Ircam – STMS – RepMus - UMR 9912

benny.sluchin@ircam.fr

Mikhail Malt

Ircam – STMS – RepMus - UMR 9912

mikhail.malt@ircam.fr

## ABSTRACT

This research explores the performance of John Cage's *Solo for Sliding Trombone* using artificial intelligence (AI) generative tools within the Somax2 environment. By integrating AI agents as virtual performers and employing techniques like "coloring the silence" and "expansions," the project investigates the interplay between human interpretation, AI-assisted performance, and Cage's concepts of silence, indeterminacy and unintentionality. The research highlights how AI can recontextualize musical relationships, creating "listening topologies" that transcend traditional linear structures. This approach, termed "playing with music," challenges conventional performance practices while raising crucial questions about copyright, authorship, and the ethical implications of AI in musical creation.

## 1. INTRODUCTION

This text presents an artistic performance research experience, concerning the performance and the use of AI through generative computer agents. Our main goal was to evaluate the influences that the use of them can have in the musical interpretation of an open work. For this we will focus on Cage's *Solo for Sliding Trombone (Concert for Piano and Orchestra)* [1] performance, with the help of technology, in particular the use of the Somax2 environment [2]. This artistic research was done in two main parts. The first being the musicological study of the work, of Cage's concepts, and the design of a computer interface for the live performance of the work, a recall from a former study [3].

The second part, which mainly concerns this communication, is focused on the use of Somax2 as a musical partner in the performance. In this specific case, the use of IA, in

the performance of open works, emerged from our working sessions as artists' consultants in the Somax2 (REACH) project. In this context we used different works for testing the software. Open-form works were part of the musical material used. Therefore, the present artistic research, is a natural development of the above-described work.

This artistic research resulted in a set of improvised performances, presented in a box set with 7 tracks (Figure 1)<fnref n="1" />. Each box (USB flash key) is unique, presenting a subset of the various performances, one of each realization. To ensure accurate tracking and attribution, we developed a computer program that numbers each USB key by copying a randomly selected performance of each realization. Our calculations indicate that there should be approximately 29,000 unique versions. We hope people enjoy discovering.

<figure><img src="image_2.png" /><figcaption>Figure 1: The Cage's Box</figcaption></figure>

## 2. JOHN CAGE SOLO FOR SLIDING TROMBONE, A COMPUTER-ASSISTED PERFORMANCE APPROACH

### 2.1. The Concert for Piano and Orchestra

The *Concert for Piano and Orchestra* (1957–58) marks a decisive step towards the definition of the notion of “indeterminacy” and appears to be one of the most important works of John Cage, a milestone in his path. For the first

Copyright: © 2025 First author et al. This is an open-access article distributed under the terms of the *Creative Commons Attribution License 3.0 Unported*, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

<footnote n="1">¹ https://youtube.com/shorts/eJ3SSbJl5k - Teaser.</footnote>
time, control over decisions regarding all aspects of the music is given to interpreters. Each performance may well sound different, and duration may vary each time. It is not a "Concerto for piano and orchestra," but a chamber ensemble piece whose instrumentation is to be defined at each performance. There are parts for thirteen instruments, a solo for piano, and a part for a conductor. There is no relationship or coordination between the individual parts. Any portion of the parts (including "void") may be chosen to be played. A version of Concert may thus have any number of these instruments, including none, which will, in that case, be a silent version, as in 4'33" (1952).

## 2.2. Performing Concepts

In John Cage's Concert's performance notes, four concepts are highlighted: Silence, Indeterminacy, Chance, and Unintentionality.

### 2.2.1. Silence

In connection with his encounter with Zen Buddhism [4], Cage rethinks his understanding of music. As a result, he composes 4'33" [4], a work whose abandonment of intentional sound production drew controversy to his compositions and methods. Cage spoke of silence in a new and positive way. It has some importance in the creation of structure, silence is viewed not as an absence of sound, but as a presence filling an acoustic space. At first, Cage developed a structural concept of silence, considering it as an absence of sound helping to structure the music by its alternation with sound. The silence between the sonic events (Called "notes" by Cage) gave the work its cohesion. "Formerly, silence was the time lapse between sounds." [6]

In Concert's instrumental parts' instructions, Cage asks: "All notes are separated from one another in time, preceded and followed by a silence (if only a short one)." [1] Later, Cage adopted a spatial concept of silence, in which it was constituted of all the ambient sounds that together formed a musical structure. Finally, his concept evolved towards viewing silence as non-intention. Both sound and silence would exist only in the non-intentional manner of nature [7]. Silence will be considered as an aesthetic object as well as a concept.

### 2.2.2. Indeterminacy

The principal of indeterminacy allows the performers to work independently from each other. In this way, the musician, ignoring the output of his/her fellow musicians, will concentrate on their own part and the set of instructions, which imposes concentration in spite of the high degree of freedom involved [8].

"Bringing about indeterminacy is bringing about a situation in which things would happen that are not under my control." [9]

Another meaning of indeterminacy for Cage is the fact that the final result is not controlled by the composer himself and the result is partially produced by a chain of performers' unintentional choices.

### 2.2.3. Chance

For John Cage, "chance" is the set of random or non-determined processes used in the composition itself. In this way, he applied the concept of non-intention in the choice of musical material in his own composition process.

"Variation in gongs, tom toms, etc. and particularly variation in the effects on pianos of the use of preparations, prepared me for the renunciation of intention and the use of chance operations." [10]

While chance is related to the compositional process, indeterminacy is related to the composer's lack of control of the performance.

As James Pritchett writes:

"In Cage's terminology, 'chance' refers to the use of some sort of random procedure in the act of composition. ... 'Indeterminacy,' on the other hand, refers to the ability of a piece to be performed in substantially different ways - that is, the work exists in such a form that the performer is given a variety of unique ways to play it." [8]

This clearly shows the difference between these two concepts.

### 2.2.4. Unintentionality

We find the genesis of the unintentionality concept in this quote by Cage:

"Improvisation ... that is to say not thinking, not using chance operations, just letting the sound be, in the space, in order that a space can be differentiated from the next space which won't have that sound in it. I'm perhaps too young at this work to know how to describe it." [10]

The unintentionality concept is the idea that a performer produces sounds, musical events without intention, aim, purpose, reason or given meaning. As Cage tells us, it comes from his Zen Buddhism studies:

"... it was rather my study of Zen Buddhism. At first, my inclination was to make music about the ideas that I had encountered in the Orient. But then I thought, instead of talking about it, to do it; instead of discussing it, to do it. And that would be done by making the music nonintentional, and starting from an empty mind." [11]

## 2.3. Computer Interface Modeling

How could one help the player, as much as possible, to perform the score in the context of "indetermination" and "unintentionality"? In what manner could one enable him/her to represent the Cage's musical thought?

It is the predetermination of the freedom relationship that proves most problematic for the player. Even if we find very hard instrumental passages, the main difficulties are: making the choice of when and what is to be played, what order to choose for the sonic events, the amount of silence to insert between the events, and all this while ignoring the output of the other musicians involved. It has to be kept in mind that by the absence of intention, one should also ignore what one is about to perform. This means that the entire score should be at the player's disposal, and that s/he will make up their mind intuitively and spontaneously.
One possible solution is to provide an adapted interface. Here, the choice is not only of timing but also of the material itself. Three kinds of interfaces (A, B, and C), ways of displaying music, were proposed, but as it was already shown in a former paper [3], we only present here the interface used for this artistic research.

### 2.3.1. *Interface C*

Figure 2 presents the interface used, where we display the events in time. With this interface, it is possible to build scores generated algorithmically, on the fly, the “elements” of the score being reorganized according to various calculation modes.

<figure><img src="image_3.png" /><figcaption>Figure 2: Interface C (violoncello score)</figcaption></figure>

Calculation procedures are based either on the “instructions,” given by Cage to the performers, or on other methods enabling them to reorganize and give “directions” to the musical material. A setting window (Figure 3) allows changing the time displayed by page and some parameters for the score generation, like the total length of the piece. Cage indicates: “...given a total performance time-length, the player may make any program (including additional silences or not) that will fill it.” [1]

<figure><img src="image_4.png" /><figcaption>Figure 3: Setting Window for the Control Interface</figcaption></figure>

In addition to the idea of freeing the player from the physical constraints of the paper score, and of taking into account “Indetermination” and “Unintentionality,” this interface also makes it possible for the player to prepare her/himself more efficiently for the various changes of instrument configuration and the various playing modes. Furthermore, it enables the interpreter to use their own will at the moment of performance, by choosing to play or not the proposals presented.

## 3. WHAT IS IT SOMAX2?

### 3.1. Somax2² Introduction

Somax2 is an advanced real-time interactive music system developed by IRCAM (Institut de Recherche et Coordination Acoustique/Musique), in the ‘Représentations Muscale’ Team, in Paris. It is designed to assist musicians and composers in creating music interactively by using AI and machine learning. Somax2 builds upon the original Somax platform and incorporates several enhanced features aimed at musical improvisation, accompaniment, and composition. Some Somax2 key features:

* Generative AI based on Machine Learning. Somax2 analyzes live musical inputs in real-time, capturing essential characteristics such as pitch, time pulse phase, chroma vectors, dynamics, and MFCC (Mel-Frequency Cepstral Coefficients) vectors.

* Interactive and reactive co-improvisation. Somax2 allows interaction between musicians and a computer system, where the machine reacts in real-time to the music played by the performer, based on probabilistic models and machine learning algorithms.

* Adaptive Interaction. Somax2 can adapt its musical responses based on the style, tempo, and mood of the input, providing an experience akin to playing with a responsive human musician.

Several papers describe how Somax2 works ([2], [12], [13], [14]). However, we would like to make a more global analysis of its characteristics.

### 3.2. How Somax2 Works, in a Nutshell

The general Somax2 approach [2], based on n-gram and SOM (self-organized maps), is very close to the OMax [15] and Dyci2 [20] model, based on the Oracle Factor, to recombine music, going beyond simple rearrangement. These generative models are centered on the OMax paradigm: *Listen, Learn and Generate*.

#### 3.2.1. *From a technological and scientific standpoint.*

Somax2 operates as an interactive music generation system that combines principles from signal processing, machine learning, probabilistic modeling, music information retrieval and human-computer interaction.

Somax2 uses real-time and non-real-time musical inputs from various sources, such as MIDI controllers, audio signals, or DAWs (Digital Audio Workstations). Using machine listening algorithms, Somax2 analyzes the input signal and extracts multidimensional musical features (pitch, chroma vectors, dynamics, pulse phase, and MFCC). Revealing sequential patterns of harmonic, timbral and tonal similarities. “Chroma vectors,” which capture the

<footnote n="2">² http://repmus.ircam.fr/somax2</footnote>
harmonic structure of sounds; MFCC, which captures the timbral characteristics of sounds; and pitch analysis, which reveals textures that share tonal qualities, creating a “web” of connections across the piece. This is the *listening* phase. Self-Organizing Maps (SOMs) and Markov Models are used primarily for creating a latent space representation of musical data, particularly for chroma features. A SOM is trained on the extracted chroma vectors, from the musical corpus, learning to organize these vectors into clusters, i.e. neurons representing similar chroma profiles. This is the *learning* phase. In other words, we can say that the analysis, from the “listening” phase, creates a multi-dimensional pathway where different sections are linked by their tonal, timbral and textural similarities, rather than their position in the original sequence. The system can navigate through the latent space, moving from one neuron to another to generate harmonic progressions or transitions. The coordinates of the activated neurons on the grid can be used as input to other generative agents. The Markov models, particularly variable-order ones, are used to capture sequential dependencies in the music listened, and to build models for each analyzed musical feature. This is the *generative* phase.

**3.1. Why Somax2 and Cage's Solo for sliding Trombone?**

A core component of Somax2 is the “corpus,” a high-dimensional representation (e.g. a state-space model), a unified representation that captures relationships among analyzed audio features, in and *outside of time*. This corpus can be built, *outside of time*, from pre-existing music, in MIDI or audio formats, or in real-time audio streams. Somax2 performs similarly to cognitive processes seen in humans, such as:

* Perception: Capturing and interpreting sensory input.

* Learning: Developing models of musical behavior.

* Memory: Retaining and applying contextual knowledge. The SOM and the variable-order Markov internal graphs act effectively as a memory space (memorizing Musical Knowledge), encoding the structural and stylistic features of the input dataset.

* Reaction and Prediction: The system's navigation through the SOM, and the Markov graph, is influenced by the immediate musical context, ensuring a contextual response. It anticipates future events in a performance.

* Creativity (or novelty): Generating novels and contextually appropriate combinations.

These features make Somax2 not only a technical tool but also a cognitive collaborator in music-making, a co-improviser. Somax2 simulates the social aspects of music-

making, where performers listen, react, and co-create. It enables a musical "conversation," balancing imitation, contrast, and complementarity in its interactions<fnref n="3" />. Considering Cage's *Concert for piano and orchestra*, as an unintentional superposition of musical material, played by a variable number of performers, *Solo for Sliding Trombone* becomes to be a good candidate to explore the use of artificial agents in musical performance.

**4. PERFORMING AND RECORDING SOLO FOR SLIDING TROMBONE**

**4.1. The Performative and Artistic Research**

In our research (musicological, performative, and artistic), step by step, we started to try different realizations of this work. First, adding “artificial agents” as virtual players, and subsequently adding synthesized electroacoustic material layers. Progressively we found a path, in these multiple experiments, that allowed, as much as possible, to keep a proximity to the original work, exploring the limits of the rules and constraints indicated by Cage (Figure 4).

<figure><img src="image_5.png" /><figcaption>Figure 4: Genealogy of *Realizations* of these Recordings</figcaption></figure>

A total of 40 recordings were made, with an average of 5 to 6 versions of each *realization*. As each *realization* was performed, an effort was made to consider a “Cagean” aesthetic.

**4.2. The seven tracks and the “colored silence”**

The seven tracks we propose (Figure 1), concern different performances of Cage's *Solo for Sliding Trombone realizations*: following the composer's instructions as closely as possible (tracks 1 to 4); passing by “expansions” (tracks

<footnote n="3">³ A further comparison with Dyci2 [20] could be of useful interest.</footnote>
4 to 7) – performances where we allowed ourselves some freedom concerning the work, but trying to follow our understanding of the aesthetic and musical context. We can consider the sequence of the seven tracks, as a progression starting with the most stripped-down version, *Realization I*, represented by Track 1, for an acoustic trombone, and gradually building up to more complex versions, using the possibilities offered by Somax2 and the electronic tool, *Realization VII* represented by Track 7 (See Figure 4). In all tracks, Benny Sluchin uses the performance-assistance tool described in section 2.3.

The track titling uses the following notation: `0y_0x`, where “y” is the track number and also the *realization* type relative to *Solo for Sliding Trombone*, and “x” is the version of that performance in the set.

### 4.2.1. Realizations

**Track 01_0x** is an acoustic version, the trombone is solo, as close as possible to the constraints and rules indicated by John Cage.

**Track 02_0x** is a four-trombone version. The acoustic instrument plus three trombones, played by three Somax2 agents. The materials played by Somax2 agents are Benny Sluchin's recordings of *Solo for Sliding Trombone* materials, hence the homogeneity of the timbre. For the Somax2 agents, there was only a slight control of the probabilities of the occurrence of the events and dynamic control, so as to sculpt a form, and the overall level.

**Track 03_0x** is a version for four trombones. However, we took the liberty to add some reverberation. This realization opened the path for us to the subsequent expansions.

### 4.2.2. Coloring the Silence

The discussion of silence will be limited to the context of *Concert for Piano and Orchestra* and *Solo for Sliding Trombone*. A broad study of this concept is extremely passionate, but obviously beyond the scope of this paper.

"Coloring the silence" what does it mean? In the words of John Cage: "*There is no such a thing as silence*" [16]. Silence, in Cage's context, is everything that happens outside the performance, i.e. the soundscape of the performance space (see also section 2.2.1). Silence is, in general, always the interval, with low-intensity sounds, between main sources, which our cognition regards as being principal. The opposite would undoubtedly be considered noise by others.

Even in an anechoic room (where room effects are highly reduced), there is not absolute silence. In essence, we are hearing our inner sounds (tinnitus, breathing, heart beats and blood flow). Silence is a background in the sound perception. Silence is a layer in our whole soundscape perception. As already said, silence is a structural element in this work. On a number of occasions, when Benny Sluchin was performing the work, in a solo acoustic version, we heard during the “silences,” cars, discussions, and other events outside the performance space. From a musical point of view, Benny has always tried to “play the silences.”

However, if he succeeded in a rhythmic, temporal, dynamic or intentional point of view, the “quality,” the timbre and the “texture” of such silence depended upon the time and place. A sonic background always remained.

Here, we took advantage of a breach in Cage's instructions. While he tells us what to do and what not to do with the single events, he says nothing about silences. Instead of leaving this sonic background to chance, we opted to manage, to generate and modulate it. At the beginning, in these silences, we started to keep the remaining reverberation applied to the Somax2 agents, as a way to give a fairly more body, more space to the whole. But the electroacoustic tool allows modulating and dynamically changing the relationships between the original sound (the dry) and the reverberated sound (the wet), and also changing the reverberation timbre quality. We started to “color the silence.” Originally, it was simply a way to build a space. Later, in this space, these colors gained presence and became foregrounds. From remaining reverberation to synthetic sound layers, it was just a step. As the synthetic sounds processes we used, were based on detected pitches and “chroma vectors,” the generated electronic background became organic with the acoustic sounds played, avoiding too much discrepancy between sound and silence.

### 4.2.3. Expansions

**Track 04_0x** inherits the evolution of *Realization III* by using the possibility of playing *Fontana Mix* (1958) with the work. This option was used in earlier performances of *Concert*, under Cage's guidance [17]. Here the configuration is as follows: The acoustic trombone and the first two Somax2 agents play *Solo for Sliding Trombone* materials, while the third agent performs *Fontana Mix*. We added a layer of synthesis to continue “coloring the silence,” each time in a more complex way. The synthesis parameters are controlled, on the one hand, in real-time analysis of the acoustic trombone, but also by Mikhail Malt, who controlled output levels, the occurred event probability, rendered by Somax2 agents, “masked” positions of the agents, as well as other synthesis parameters, which go beyond the scope of the present text. This *Realization*, let's say, is a hinge between strict adherence to the constraints and rules indicated by Cage and a freer interpretation. The electronics, which were merely a “color of silence,” gradually began to take on their independence.

**Track 05_0x**, strictly follows the previous *Realization IV*, adding Cage's voice, as an extension of the third Somax2 agent (that still having *Fontana Mix*). This track continues the transition begun in the previous version, or track 4, with a form that drives the complexity towards the appearance of Cage's voice, towards the end. The source of this voice is the digitization of *Empty Words*, Part IV (released as a Vinyl LP in 1987). The synthetic layer continues with more complexity.
**Track 06_0x** takes the *Realization III* and uses a prepared piano<fnref n="4" /> on the third agent. For the “prepared piano,” we copied the first thirty bars of the *First Interlude* from Cage’s *Sonatas and Interludes*, for prepared piano (1946–1948). From the copied file, we generated a MIDI file and used it to control a virtual prepared piano (Following Cage’s instructions) in a DAW (Digital Audio Workstation). The result was rendered in an audio file used in a Somax2 agent.

**Track 07_0x** takes up all previous configurations with maximum freedom. Here, the shift is total. The silence that was in the background, an element of contrast in response to the acoustic elements, becomes colored, and at certain moments is the foreground. The first agent contained Cage’s *Cartridge Music* (1960 version), the second, *Fon-tana Mix* and Cage’s voice and the third agent, the same *First Interlude* from Cage’s *Sonatas and Interludes* for prepared piano (1946–1948), used in **Track 06_0x**.

All tracks are derived from improvised live performances by Benny Sluchin on trombone and Mikhail Malt on electronics (Somax2 agents and audio synthesis).

#### 4.2.4. *The recording space*

All the tracks are in binaural format with a spatial positioning shown in Figure 5. This is the reference in terms of spatial configuration. It is worth noting the contributions of Sylvain Cadars, who engaged a creative approach in the mixing process, effectively integrating the various elements through an adjustment of their internal dynamics to spatial movements.

<figure><img src="image_6.png" /><figcaption>Figure 5: Spatial positioning of all sound sources</figcaption></figure>

# 5. DISCUSSION

From this artistic performative research, several main subjects arouse.

## 5.1. What Somax2 offers to our listening?

Traditional music follows a sequential, linear, time-based progression from beginning to end. Music is one of the “arts of time.” Somax2 redefines this paradigm by

mapping a musical work based on sonic and textural relationships, creating “listening topologies.” Paths that were originally far apart can now be experienced side by side, linked by sonic similarities rather than by sequence, transforming the experience into a timeless understanding of the musical work. The non-linear approach creates surprising juxtapositions of themes, increasing the listener’s awareness of the musical works’ deeper connections and revealing hidden symmetries. By reorganizing sounds in this way, Somax2 essentially suspend the timeline of a musical work, disrupting the conventional linear paradigm, allowing the listener to perceive the music as if s/he was exploring a multidimensional “gallery” of sound. Rather than following a preset narrative, Somax2 offers potential new experiences, paths, and topologies. Like a multiverse with different parallel realities, it generates alternate versions of the musical work along different sonic paths. Letting the listener to engage with the musical work from different listening perspectives, with each path offering a different interpretation. By reordering a composition based on sonic similarities, a piece of music is distilled to its essence, highlighting recurring musical gestures and harmonic themes that define its character.

The above-described process, can act as a kind of “summary,” grouping related sounds together and bringing the core elements of the composition to the fore. Allowing the listeners to hear it almost as a condensed version, focused on its most characteristic sounds.

This “wrapping” of the music, conserves its sonic material while altering its form, allowing the listener to experience the contours and textures of the musical work independently of its original narrative flow.

Thus, the composition is transformed in a more abstract, conceptual form that transcends traditional sequential musical structures, like an “outside of time” structure, as defined by Xenakis [18].

## 5.2. “Playing music” and “playing with music”<fnref n="5" />

“Playing music” involves the execution of established compositions, adhering to notations and stylistic conventions. This approach emphasizes accuracy and fidelity to the score, while musicians work to interpret the intentions of the composer. The goal in this process lies in the artistry of performance. Musicians often find fulfillment in mastering complex techniques and presenting music with clarity and nuance, fostering a deep connection with the musical work and its public.

However, the use of Somax2 introduces the concept of “playing with music,” which adds another layer of exploration that goes beyond the scope of conventional performance. This approach encourages us to engage with the score and the music itself, in an interactive and improvisational way, allowing for spontaneity and personal expression, which was beneficial for us and we hope the public.

<footnote n="4">⁴ The virtual piano used was the IRCAM prepared piano, ©Ircam, ©UVI. https://www.uvi.net/fr/pianos-keyboards/ircam-prepared-piano-2.html.</footnote>

<footnote n="5">⁵ This chapter was inspired by György Kurtag, who we would like to thank for our discussions on this issue.</footnote>
By modifying established conventions, playing with
rhythms, experimenting with dynamics, timbres, colors,
recombining a recorded performance, we could reinterpret
the music, bringing our own special insights to the table.
This approach brought new life to a familiar work and en-
gaged audiences in a fun and surprising way. This idea lets
the past and present talk to each other. "Playing music"
and "playing with music" reflected the dynamic nature of
artistic expression. It showed us how we could explore and
innovate while still honoring tradition. Music is a living
thing that changes and motivates us. This duality encour-
ages celebrating the past and to contribute to the musical
expression.

5.3. "Playing With Music" as a Catalyst Approach

"Playing with music" has always been a way for composers to create and innovate. This approach lets musicians try new ideas, sounds, and structures that challenge the norm. From folk music to modern compositions, the mix of structured performance and creativity has shaped music through the times. By changing existing music, composers and performers can create new pieces that fit their artistic vision. Many cultures have long used improvisation in music. This practice encourages both individual expression and collaboration, resulting in different performances each night. Blending spontaneity and structure creates unique compositions that are reflected in live performance. "Playing with music" also means changing traditional forms and genres, rebuild it in new ways. Throughout musical history, musical variations, improvisation and the process of citation, exemplify a form of "playing with music," as composers modify, expand, and reference existing works to explore their creative potential. From Bach's *Goldberg Variations*, Beethoven's *Diabelli Variation*, jazz practice, Lukas Foss's *Baroque Variations*, Berio's *Sinfonia*, to Lang's *The Little Match Girl Passion*<fnref n="6" /> postmodern reinterpretation of Bach's *St. Matthew Passion*, this practice celebrates the dynamism of music. By reimagining familiar material, composers create a kaleidoscope of sounds that remain rooted in the original idea, inviting listeners to discover themes through fresh perspectives and showcasing the inherent flexibility of music itself.

Through the use of Somax2, “Playing with music” be-
comes a philosophy that shapes how we perform, how we
listen. It encouraged us to explore and be creative. In our
opinion, this mix of experimentation and structure keep the
music alive and relevant. These points illustrate the differ-
ent ways in which we can engage with the concept of
“playing with music,” highlighting the creativity and inno-
vation that arise from this dynamic interplay, from this co-
creative interaction [19].

5.4. Authors' Rights and Ethical Dilemma in
"Playing with Music"

The practice of “playing with music,” which encourages reinterpretation and improvisation, gives rise to complex questions regarding authors’ rights and ethical considerations. The core of this issue is the conflict between respecting the composer’s initial vision and the desire for artistic freedom. When musicians take liberties with established works—modifying melodies, rhythms, or harmonies—they must navigate the legal landscape of copyright laws, which are designed to protect the intellectual property of creators. We sustain that creative reinterpretation can breathe new life into a musical work. Nevertheless, that such alterations can dilute the original work’s integrity and undermine the rights of the composer.

Copyright laws vary by country but usually give authors
the right to reproduce, distribute, and perform their works.
These laws make it hard for musicians to experiment with
existing music. Sometimes, you need permission from the
copyright holder to create something new, it can take a
long time and cost a lot of money. Being afraid of getting
into difficulty can stop musicians from being creative.
They might not want to try new things because they don't
want to copy other people's work, raising some important
questions:

* How much can you change a piece of music before it's illegal?

* How can you be certain you’re doing the right thing when you’re using other people’s music?

Furthermore, the ethics of “playing with music” goes be-
yond legal issues. Musicians must consider the composer’s
legacy and the context in which the work was created. Re-
interpreting a musical work can be seen as an act of respect
or disrespect. If one changes a traditional folk song without
understanding its cultural significance, it could be seen as
appropriation, showing how significant it is to consider
context and be sensitive when artists reinterpret works.

Ultimately, the challenge is finding a balance between cre-
ative freedom and respect for authorship. Musicians can be
ethical by acknowledging the original composers, and un-
derstanding the cultural context of the music they play.

6. CONCLUSIONS

This artistic research, exploring the use of computer musical agents, in the performance of open works, could highlight several aspects of live interaction with technology, given the use of computer agents as genuine musical partners. Somax2, by redefining musical relationships through sonic and textural connections, invites listeners to experience compositions as multi-dimensional “listening topologies.” This non-linear approach disrupts traditional linear listening, allowing for deeper engagement and a more holistic understanding of the musical work.

<footnote n="6">⁶ https://davidlangmusic.com/music/little-match-girl-passion/
2024/10/08.</footnote>
"Playing with music," encompassing both traditional performance and innovative reinterpretation, lies at the heart of this exploration. While traditional performance prioritizes fidelity to the score, "playing with music" encourages experimentation, improvisation, and the reimagining of existing works. In our context it allowed us to explore and develop the concept of "coloring the silence."

However, the practice of “playing with music” raises important ethical considerations and legal balance between creative freedom and respect for the original composer work. By acknowledging the source material, understanding its cultural context, and seeking appropriate, when necessary, musicians can navigate through these complexities while enriching the musical landscape with innovative interpretations.

Ultimately, “playing with music” serves as a catalyst for artistic growth, encouraging dialogue, innovation, and a deeper appreciation for the enduring power of musical expression.

As said earlier, this research, and the use of AI agents to perform open musical works, emerged from our working sessions as artists' consultants in the Somax2 (REACH) project. Further research will include comparative study of human versus machine performances and audience reception as well.

This research is part of the REACH project, supported by the European Research Council under Horizon 2020 program (Grant ERC-2019- ADG #883313) and MERCI project, supported by the Agence nationale de la recherche (Grant ANR-19-CE33-0010).

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