1. A brief introduction to Studio PANaroma
1.1. Studio PANaroma: three decades of electroacoustic research and creation at UNESP
Established in 1994 by composer and researcher Flo Menezes, Studio PANaroma has become one of Latin America’s leading centres over the course of thirty uninterrupted years. The Studio’s mission, from its very beginning, was to foster research, creation and dissemination of electroacoustic music. Officially affiliated with the Department of Music at the Institute of Arts of São Paulo State University (UNESP), the studio operates within the framework of a public university that offers high-quality, tuition-free higher education to students from across Brazil.
Studio PANaroma occupies a dedicated building adjacent to the main Institute of Arts facility. Its purpose-built architectural and technical infrastructure is tailored to meet the complex demands of composing, recording, analysing and presenting electroacoustic music.
At the heart of the facility lies a multi-use space equipped with a 16-channel speaker diffusion system. This central room, known as Studio A (Figure 1), functions simultaneously as a multichannel composition studio, a classroom and a control room for recording sessions with an additional stereo system for mastering. Its large glass windows allow visual communication with the adjoining recording space (Figure 2), facilitating integrated production workflows.
Studio A at Studio PANaroma.
Recording room at Studio PANaroma.
In addition to these primary spaces, the studio houses four independent workstations reserved for students and researchers involved in ongoing projects. Each one is equipped with Apple computers and 4.1 audio systems, providing an environment conducive to focused sonic experimentation and compositional research. A separate room is designated for faculty and the studio’s artistic director, while another space is dedicated to the studio’s technical engineer, who oversees equipment maintenance and provides support for both pedagogical and artistic activities.
Studio PANaroma also manages, in collaboration with the university’s theatre, a large-scale fixed diffusion system known as PUTS – an acronym for ‘PANaroma/UNESP: Teatro Sonoro’ (Figure 3). This system comprises 30 speakers arranged across three octophonic tiers, four additional loudspeakers on stage and two subwoofers and is permanently installed in the theatre space. The PUTS system was founded by Flo Menezes in Reference Menezes2002 and enables immersive electroacoustic performance and is often augmented during major events such as the São Paulo International Biennial of Electroacoustic Music (BIMESP) and the T-Son concert series, both of which are representative outreach initiatives of the studio.
PUTS Loudspeaker orchestra during the XV BIMESP (stage setup).
The T-Son series, held monthly, serves as a platform for the dissemination of electroacoustic music both within and beyond the university community. All concerts are free of charge, helping to democratise access to this specialised repertoire. Each event typically unfolds over two days. T-Son concerts are structured as immersive, multi-day events that integrate pedagogical, technical, and artistic activities. Students participate in the set-up and operation of the loudspeaker orchestra, gaining hands-on experience with professional equipment and concert logistics. Classes are temporarily relocated to the venue, allowing a broader audience to engage with historically and aesthetically significant electroacoustic works. These events often include educational activities for visiting groups, rehearsals with spatialisation, and evening performances. T-Son also serves as a platform for premieres by current and former students, as well as guest artists from Brazil and abroad.
A key feature of Studio PANaroma is its autonomous management model, which grants the teaching and artistic staff a considerable degree of independence in defining research agendas, usage policies, and aesthetic orientations. This autonomy has been instrumental in establishing the studio as a site of sustained innovation and as an active participant in international networks of electroacoustic music production, particularly across Latin America and Europe.
Over the years, Studio PANaroma’s development has been supported significantly by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), whose grants have enabled a series of artistic-scientific research projects. This support has contributed to continuous technological upgrades and deeper explorations into the intersections of musical creation and technological development.
As it marks its thirtieth anniversary, Studio PANaroma stands not only as a witness to the evolution of Brazilian electroacoustic music, but also as a dynamic platform for education, production, dissemination and critical inquiry within this musical field – actively shaping the landscape of experimental music in Latin America.
1.2. Studio PANaroma: a school of composition
Over three decades, the Studio PANaroma has been functioning as more than just a studio – it can be regarded as a veritable school of composition, grounded in a clear artistic and aesthetic vision that has been present since its inception.
Given the studio’s origins in a challenging and pioneering effort by composer Flo Menezes,Footnote 1 it is essential to briefly examine his trajectory as an artist-researcher in order to understand the type of compositional ethos that Studio PANaroma stands for.
Menezes belongs to a generation of Latin American composers who engaged directly with the European avant-garde, forging close ties with figures such as Luciano Berio, Pierre Boulez, Henri Pousseur – his doctoral advisor – and most notably Karlheinz Stockhausen, who even invited him to teach an analysis class on Stockhausen’s works at the Stockhausen-Kurse in Kürten, Germany, in 1999 and in 2001. Further reinforcing his structuralist foundations, Menezes pursued postgraduate studies under Hans Ulrich Humpert, successor to pioneering composer and researcher Herbert Eimert in Cologne, Germany. This experience deepened his engagement with (post-)serialist methodologies, which have since become a hallmark of his compositional approach.
Simultaneously, Flo Menezes cultivated strong connections with the French acousmatic tradition, drawing influence and support from composers such as François Bayle, Francis Dhomont, and Annette Vande Gorne – figures who not only influenced his thinking but also became lasting collaborators and friends.
Taking account of the artistic output produced by Studio PANaroma students over the past decades, it becomes evident that the studio cultivates a distinctive compositional approach – one that traverses diverse epistemologies and integrates aspects of both the French acousmatic tradition and the European post-serialist avant-garde to which figures such as Stockhausen and Boulez belong. This dual influence is reflected in a compositional ethos that values both the morphological richness of recorded sound and the rigorous formal structuring of musical material.
On one hand, there is a marked preference for working with concrete sounds rather than synthetic ones. Central to this practice is the use of a dedicated acoustically treated recording room, located at the heart of the studio, specifically designed to capture and manipulate sound sources with high fidelity. This infrastructure underscores the influence of the acousmatic tradition, in which the recorded sound – its morphology, indexical resonance, and spectromorphological behaviour – forms the basis of musical material.
On the other hand, compositional procedures at Studio PANaroma are often shaped by strict and unique formal guidelines governing the organisation and articulation of sonic materials. These reflect a post-serialist orientation, clearly aligned with the structural and theoretical rigour characteristic of the German electronic music school. Such a framework underscores not only the analytical precision expected of student works but also the conceptual lineage of the studio, situated at the confluence of intuition and systematisation, experimentation and formal clarity.
According to Menezes,
the new studio should also lead to experiences on Brazilian soil that could reflect and even exceed the most significant contributions of not only the German branch of elektronische Musik – notably the structural work of Karlheinz Stockhausen, but also the concrète (and typically acousmatic) side, typified by the teachings of Pierre Schaeffer. When I conceived and founded the new studio, I recognized that my intention reflected that anthropophagic spirit […]. (Menezes Reference Menezes2022: 112)
Despite the presence of a clearly defined compositional orientation, Studio PANaroma fosters a wide space for artistic individuality and stylistic exploration. Students are actively encouraged to engage with sound material in their own way and to cultivate a personal approach to composition. The pursuit of an individual musical identity is not only permitted but deeply embedded in the ethos of the studio. In this regard, Studio PANaroma provides access to a broad array of audio tools and technologies, enabling each composer to work independently in their own studio environment. As a result, the body of works emerging from Studio PANaroma is marked by remarkable stylistic diversity, reflecting a plurality of creative solutions within a shared framework of compositional rigour.
1.3. On the role of concrete sound as foundational material in electroacoustic composition
While there is a clear preference for concrete sounds over synthetic ones as the primary material for electroacoustic musical composition at Studio PANaroma, this inclination should not be understood as an exclusivist stance. Rather, it reflects an aesthetic orientation and a pedagogical emphasis that shapes much of the studio’s approach. Sound synthesis remains a valid and available creative resource, and composers are encouraged to explore it when it aligns with their artistic objectives.
The prominence of concrete sound stems more from its inherent spectral richness and acoustic detail – qualities that arise from the complexity of real-world sound phenomena occurring in physical space. Concrete sounds often carry subtle spatial cues, nuanced timbral layers, and unpredictable microvariations that are difficult to replicate or to achieve through synthesis alone. Not to mention their symbolic potential to refer to extra-musical dimensions. These characteristics make concrete materials particularly fertile for acousmatic exploration, where the ear becomes attuned to the morphological and directional features of sound in time.
When composing acousmatic music, composers usually begin their creative processes through the attentive listening and exploration of pre-existing sonic materials – akin to Duchampian ready-mades. These audio fragments, drawn from ‘recorded reality,’ serve as the initial building blocks of the compositional process and are valued for their intrinsic rhythmic motion, morphological, and directional properties. This methodology highlights the importance of listening as a generative act, where form can emerge through the engagement with sound itself rather than through pre-imposed structures or systems.
While hearing occurs automatically, without the need for focused attention, listening to musical objects involves an active, deliberate engagement. It is through this cultivated form of listening that aesthetic perception becomes heightened, as our awareness is guided by the inherent directional qualities of the sounds themselves.
Developing the ability to listen attentively to sound objects and to envision them as integral components of a musical discourse is a fundamental skill for the student-composer working in the acousmatic tradition. This mode of composition demands an indispensable and direct relationship with the sonic material, compelling the composer to focus their listening on its concrete dimensions. Acousmatic composition, therefore, involves an active search for external sonic phenomena that capture the composer’s attention and stimulate creative engagement.
This is precisely why the two sound-based research cases examined in this article prioritise the development of primary sonic materials (concrete sounds), given their fundamental function in shaping the compositional framework – often exerting greater influence than subsequent stages of elaboration.
2. Two sound-based research initiatives carried out under the auspices of Studio PANaroma
2.1. Exploring the boundaries of harmonicity and inharmonicity
The first example, which will be presented in this article, is the six-year-long Thematic ProjectFootnote 2 called Harmonicity and Inharmonicity in Instruments of the Percussion/Resonance Family in Interaction with Electronics. The project took place between 2019 and 2025. It was the result of a partnership between Studio PANaroma and the UNESP percussion group PIAP – an internationally acclaimed ensemble created in 1978 by professor/percussionist John Boudler. The research was conducted by Flo Menezes (research leader), Carlos Stasi and Eduardo Gianesella – artistic and co-artistic directors of PIAP, respectively. Besides this very successful partnership between Studio PANaroma and PIAP, the research project also involved collaborations with researchers from other distinct institutions such as Harvard University, the University of Coimbra and the University of São Paulo.
The research was funded by FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo), a public funding agency that has supported research at Studio PANaroma since its inception in 1994. For this Thematic Project alone, FAPESP allocated approximately R$2,000,000 (two million Brazilian reais), equivalent to around €300,000 (three hundred thousand euros). These funds were primarily used for the acquisition of equipment, including percussion instruments, computer hardware, and software.
The research aimed to investigate harmonicity and inharmonicity in the context of percussion-resonance instruments,Footnote 3 with two main objectives: to develop tools that enable their interaction with electronic media, and to design computational resources that, through spectral analysis, foster integration between these instruments and other orchestral families – including those governed by different morphological principles.
The research had six comprehensive goals:
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(i) a spectral analysis of core percussion/resonance instruments, focusing on their degree of harmonicity and inharmonicity, followed by the systematic cataloguing and classification of the resulting sound materials;
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(ii) the historical recovery and Brazilian premiere of landmark works of contemporary music for percussion – with or without piano and electronics (in either fixed media or live electronics formats) – that had never been performed in the country;
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(iii) the reconstruction and technological updating of the electroacoustic systems required for performing these works;
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(iv) the development of new real-time electronic tools designed to interact with this instrumental family, using spectral harmonicity/inharmonicity and advanced sound synthesis parameters as guiding criteria;
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(v) the creation of original compositions as part of the research outcomes; and
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(vi) the publication and dissemination of all project results, including public performances of both the historical and newly commissioned works.
The research was centred on the concept of harmonicity rate, a metric that indicates how much of a sound’s spectrum diverges from the harmonic series. The types of spectrum can be divided into different categories, according to the level of periodicity of the sound wave, the perception of a fundamental, and the relationship between the partials. When the partials are in ratios of whole numbers from the fundamental, the sound is essentially harmonic; when they are not related to a fundamental according to those ratios, the sound is inharmonic. According to Denis Smalley’s definition:
While harmonic spectra have a specific intervallic organization based on the vibrational properties of strings and columns of air, inharmonic spectra do not. The bell and metallic resonances are the usual examples of inharmonicity, and they suitably represent the inharmonic dilemma because inharmonic spectra can be ambiguous in that they can include some intervallic pitches. To be regarded as properly authentic, an inharmonic spectrum cannot be resolved as a single note, and its pitch-components need to be considered relative, not intervallic. As a result, continuous inharmonic spectra have a tendency to disperse into streams. (Smalley Reference Smalley1997: 120)
The family of instruments investigated in the project was deliberately selected for its wide variety of sounds, which span the continuum between fully harmonic and fully inharmonic spectra.
Twenty different instruments were recorded during the research, including various types of gongs, steel drums, Sixxens, vibraphone, and waterphone. This process resulted in 5,778 unique sound files, each of which was analysed using the Sononym Footnote 4 software. Sononym is a sample browser that facilitates the organisation and exploration of audio files based on their sonic characteristics. It offers features such as a harmonicity factor, brightness, and noisiness metrics, enabling users to sort and categorise sounds according to these parameters. The outcomes of these analyses were employed to classify each sound file systematically.
The relationship between spectral content and spatial perception was also central to the research. Recognising the significance of spatiality in electroacoustic music, all sounds were recorded in six channels, using an array of microphones strategically positioned around each instrument to capture their radiated sound fields. In addition to the multichannel recordings, stereo mixes were produced to ensure broader accessibility. Both formats are currently available to composers and researchers, accompanied by detailed documentation that includes photographs and descriptions of the instruments, the types of beaters, mallets, and other implements used, as well as the specific modes of excitation or attack (such as striking, scraping, or bowing), along with the names of the participating musicians.
Regarding the goal of premiering historically significant works on Brazilian soil, Flo Menezes selected nine landmark compositions, including the following: Mikrophonie I (1964) by Karlheinz Stockhausen, Duet for One Pianist (1989) by Jean-Claude Risset, and Six Japanese Gardens (1993–1994) by Kaija Saariaho. The presentation of these works posed considerable challenges: the researchers and artists involved had to update or reconstruct several electroacoustic devices originally designed for their performance, some of which were developed more than three decades ago. In the case of Mikrophonie I, for instance, the process required not only a detailed study of the score but also an in-depth technical analysis of the historical equipment used in the original performances (Vilani Reference Vilani2024: 106). Under the guidance of Flo Menezes, composer and musical programmer Raphael Vilani undertook the reconstitution of several original patches.
In parallel, they also developed a Max library named HIN (Harmonicity/Inharmonicity) (Figure 4), designed to support the analysis and creative exploration of spectral characteristics within the project’s framework. These tools will be presented and contextualised – both technically and aesthetically – in the following section.
Overview of the HIN abstraction library.
2.2. Interaction and live electronics in the context of Oposicantos
One of the main artistic outputs of this six-year-long sound-based research was Flo Menezes’ opera Oposicantos, which premiered on July 3rd, 2025, in São Paulo. This quasi-opera – or, as the composer sometimes describes it, ‘multimedia musical action’ – merges advanced real-time spectral analysis with a performative structure that challenges the predominant one-way logic of live electronics, in which instrumental output generates electronic response, but not the other way around.
Menezes is a composer who dedicates a significant portion of his artistic work to the creation of mixed electroacoustic music. He has also written extensively on the subject, particularly regarding the interaction between computers and performers (1997; 2003; 2014). As a composer engaged in the international electroacoustic music scene and a recognised expert in the field, he is not merely an observer of its history, but an active contributor to the expansion of its possibilities.
It is within this context that Menezes proposes a model of interactivity in electroacoustic performance that he terms retroactive scripture. This concept refers to a compositional and performative approach in which electronics, generated live through spectral analysis, feed back into the performers’ decisions in real time, transforming each performance into a structurally open and unique event.
Menezes’ retroactive scripture is closely related to Manoury’s idea of a virtual score, which was first introduced in the late 1980’s (Manoury Reference Manoury2008b). Manoury’s proposal is based on the perception that the tape (i.e. fixed-media sounds) deprives the performer of temporal freedom. In response, and in collaboration with Miller Puckette – a leading figure in the field of musical computation and the original author of the Max and Pure Data environments – Manoury developed tools that enabled performers to reclaim control over temporal structures in mixed music contexts.
In addition to this ‘freedom of performance’ in the time domain, a virtual score also aims to incorporate the physical score’s idiosyncratic duality – the simultaneous presence of both predetermined and indeterminate elements. In traditional notation, certain parameters are fixed while others are intentionally left open to the performer’s interpretation. Manoury’s proposal is to transpose this duality into the digital domain, enabling computers to participate in mixed music with a comparable balance between structure and flexibility.
As such, a virtual score allows for the performer’s interpretation (for example, speeding up, slowing down, making dynamic changes, or choosing a new tempo, etc.), while also assigning the computer a role analogous to that of the performer: it contains both fixed and indeterminate parameters and remains responsive to the performer’s actions:
A virtual score is a musical organization in which we know the nature of the parameters that are going to be treated but not always the exact value they will receive. Some of those parameters will be fixed and will not change from one interpretation to the other. Other parameters will be influenced by the capture of exterior events (a microphone, for example) which will be analyzed and treated according to certain compositional rules. Thus every score can’t be anything but virtual, because their role is to be interpreted, not to be reproduced identically. (Manoury Reference Manoury2008a).
One example of controlled indeterminacy in mixed music is the use of Markov chainsFootnote 5 , a technique employed extensively by Philippe Manoury. In certain works, the probabilities governing the Markov chains are influenced by choices made in real time by the performer. In Pluton (1987–88), for instance, the performer can choose to repeat specific chords. The more frequently these chords are repeated, the more the Markov chain responsible for generating the electronic part transforms note sequences into chords. Thus, the performer actively controls the speed and trajectory of this transformation. Additionally, the sound materials used by the Markov chains in Pluton are sampled in real time and then transposed – meaning that the performer also determines the sonic content that will feed the algorithmic processes.
Flo Menezes’ concept of retroactive scripture is situated within these broader theoretical and aesthetic premises on electroacoustic mixed music. According to Menezes, his approach introduces an additional recursive layer to the performer–machine interaction: not only does the performer influence the computer, but the real-time electronic output also shapes aspects of the performer’s musical response. This recursive interaction is not merely gestural, but structural: musical gestures by performers trigger electronic responses, which in turn generate new musical content – such as harmonic projections or gestural models – performed by instruments like a MIDI piano or interpreted vocally. The performers, then, become active respondents to a musical environment that they themselves have partially set in motion, making decisions during the performance that alter the formal or textural trajectory of the piece. This cycle of influence places the electronic layer not as an extension of the acoustic instrument, but as an agent of structural determination within a chamber-music-like exchange between human and machine. In Menezes’ own words:
For years, in mixed electroacoustic music, I have been interested in procedures that allow the results of real-time electronic processes to reverse direction and return to the performers. By perceiving this or that transformation stemming from their own gestures, performers can then influence the unfolding events in the score. This is what I define as retroactive scripture. (F. Menezes, personal communication, July 11, 2025)
The technical realisation of this concept, in the case of Oposicantos, was enabled by the creation of the HIN (Harmonicity/Inharmonicity) library for Max/MSP, developed by Raphael Vilani under the supervision of Menezes.
Rather than coding fixed patches for each specific piece, Vilani designed a modular set of abstractions that could be flexibly combined. This structure allowed for a more fluent and reusable approach to real-time analysis, facilitating integration with a variety of compositional scenarios. The HIN library includes descriptors that evaluate harmonicity and inharmonicity, modules that convert spectral data into pitch information (in midicents), harmonic interpolators, and arpeggiators with velocity mapping. It also incorporates techniques developed by Menezes in previous works and theoretical writings, such as cyclic modules (Menezes Reference Menezes2013: 94) and proportional projections (Menezes Reference Menezes2013: 98).
Among its notable components is a module named S3F (Spectral Synthesis from 3 Frequencies), inspired by a technique used by Miller Puckette and Philippe Manoury (Manoury Reference Manoury2015) to generate complex inharmonic spectra. While originally implemented in synthesis contexts, Vilani reimagined it in symbolic terms, allowing the process to be used in score-based or algorithmic composition (Figure 5). This feature reflects the project’s broader ambition to foster a dialogue and a critical proposal of real-time electroacoustic music making, grounded in local technical and aesthetic priorities, positioning Studio PANaroma as a site of innovation that is internationally engaged.
hin.s3f abstraction in Max MSP.
In alignment with the project’s goal of fostering the creation of new works, eleven composers were invited to write pieces based on the sound objects recorded throughout the research. The resulting repertoire includes acousmatic, instrumental, and mixed compositions. Most of these works were premiered during the XV BIMESP (International Biennial for Electroacoustic Music of São Paulo), a major festival organised biennially by Studio PANaroma since its first edition in 1996.
Due to the amplitude of its goals, the research generated significant impacts across multiple fields, including musical computing, acoustics, contemporary musicology, performance, composition, and electroacoustic music. All proposed goals were successfully accomplished: the recorded sound materials, the HIN package, and the documentation of both new and historical works have been made publicly available.Footnote 6 The research also expanded the reach of these works through public performances and recordings, thus contributing to their broader dissemination. Beyond its immediate outcomes, the research offers a substantial contribution to both musical composition and the digital processing of sounds and spectral data. Its comprehensive sound bank is expected to remain a valuable resource for future research and artistic endeavours.
2.3. From harmonicity to Sonoclisis: a new line of inquiry at Studio PANaroma
In 2024, we formally established SOMNIUM – Estudos em Música Eletroacústica, the official research group of Studio PANaroma. Its primary objective is to promote academic research and publications by postgraduate students affiliated with the studio. The group’s name references Somnium, the visionary novel by Johannes Kepler, while also functioning as an acronym: Sonus – Ousia – Meditatio – Noesis – Inventio – Uditio – Musica – a sequence that evokes a philosophical and poetic engagement with sound, listening, and composition.
SOMNIUM is currently launching a new line of inquiry that, while distinct in focus, is partially informed by the outcomes and theoretical developments of the aforementioned Thematic Project. Whereas the earlier project concentrated on the study of harmonicity and inharmonicity in percussion instruments and was grounded in aesthetic premises more closely associated with the domain of mixed music – particularly drawing on Flo Menezes’ notion of écriture retorative – this new research direction explores the recording and analysis of sounds generated by the physical coupling of vibrating bodies, adopting a different theoretical orientation while maintaining a similar research structure, including the development of a sound corpus, computational tools, and new compositional works.
This new research project introduces the neologism Sonoclisis to designate a long-standing practice of sound creation based on the physical coupling of vibrating bodies. While the technique itself is far from new – having appeared throughout music history in various acoustic configurations – it gained particular prominence within the experimental traditions of the twentieth and twenty-first centuries, where the search for novel sonic materials and the expansion of instrumental possibilities became central concerns. The term Sonoclisis, derived from the Latin sonus (sound) and Greek klisis (inclination, leaning), proposes a conceptual and poetic framework for naming this mode of sonic emergence, grounded in physical interaction, resonance, and energy exchange between sounding bodies.
Classic examples include the prepared piano, in which metallic or wooden objects are inserted between the strings, generating compound timbres that arise from the interaction between the piano mechanism and foreign materials. Another case would be placing a crotale on a timpani head: when the timpani is struck or subjected to a pedal glissando, the resulting sound is not simply a blend of both instruments but a fused spectral entity – one that emerges precisely from their physical and vibrational coupling.Footnote 7 These instances exemplify how Sonoclisis can emerge from very distinguished approaches and how it privileges the generative role of material interactions, treating them not as byproducts of performance but as primary sources of sonic invention.
The search for a name to delineate this specific field of investigation began with the idea of naming it resonant cross-synthesis between vibrating bodies. However, we soon abandoned the term synthesis, as it is more appropriately associated with digital contexts – where sounds are constructed from atomic units such as sine waves, grains, or other elementary components. We then explored a conceptual analogy with acoustic convolution, imagining a physical counterpart to the digital convolution process. Yet, this formulation also proved theoretically inadequate. Convolution, in its strict sense, occurs at the spectral level, involving the multiplication of frequency-domain representations. In contrast, the phenomenon we aim to investigate operates at a pre-spectral level – that is, it arises from the corporeal interaction between resonant bodies. Each body possesses its own spectral identity depending on the mode of excitation, but when two or more are combined through physical contact (direct or mediated), they generate a third, emergent spectrum – not merely the sum or the convolution of the originals, but a qualitatively new spectral entity. Only after exhausting these conceptual routes did we arrive at the strategy of coining a neologism.
2.4. Aesthetic foundations and compositional intentions in Sonoclisis
At this point, I would like to take a brief moment to speak in the first person, as the researcher and composer leading this research project. What follows is a reflection grounded in my own creative practice in the field of acousmatic music, which has fostered the conceptual orientation of this investigation. Although this article is co-authored, the present section articulates a set of aesthetic and technical considerations that emerge directly from my work with recorded sound and my long-standing engagement with écriture sur support – that is, the compositional practice centred on listening, recording, editing, and structuring sound materials in a fixed-medium setting, as established within the tradition of musique concrète and later developed through the acousmatic paradigm (Chion Reference Chion1991; Bayle Reference Bayle1993). It is from this perspective that the Sonoclisis project takes form: not only as a programme for capturing and classifying acoustic phenomena from the coupling of sounding bodies, but as a way of thinking and composing through sound.
Several vectors have shaped the direction of this research. First, a strong inclination toward working with concrete rather than synthetic sound materials has been a defining aspect of my compositional practice. As discussed in the first section of this article, the PANaroma composition school places particular emphasis on the primary elaboration of recorded sound. In this context, the theoretical contributions of Pierre Schaeffer (Schaeffer Reference Schaeffer1966, 1967) and Michel Chion (Chion Reference Chion1983; Reference Chion2010), though not recent, remain both relevant and resonant: each has framed acoulogy as a domain of inquiry centred on what can be found to be musical in sound itself. Acoulogy focuses on sound as an auditory experience, investigating the mechanisms of listening, the perceptual properties of sound objects, and their musical potential within the field of hearing. It aims to ‘forge a path’ between the ‘lower’ level of raw sonic material and the ‘higher’ level of musical organisation and meaning. Schaeffer compared the relationship between acoustics and acoulogy to that between phonetics and phonology: while acoustics studies the physical properties of sound, acoulogy seeks to identify, within perceived sound, the distinctive criteria relevant to a musical language (Chion, Reference Chion1983: 94).
In other words, acoulogy does not deny the objective data of physics, but rather asks how the human ear segments, categorises, and assigns relevance to certain aspects of sound. For Schaeffer, ‘it is no longer acoustics, but not yet music’Footnote 8 (Schaeffer; Reibel Reference Schaeffer and Reibel1998: 146) – an experimental and preparatory stage, a kind of solfège of sounds, preceding musical organisation itself. Acoulogy, then, invites us to attend to the perceptual properties of sound – its mass, spectral shape, internal motion – and to treat those attributes as compositional information. This research adopts such an approach as a methodological basis throughout its development and, most critically, during its initial phase, in which the selection of materials and the exploration of their possible couplings are conceived as the foundation for generating primary sound matter: concrete sounds.
Second, although my recent compositional work has been increasingly concerned with sound referentiality – particularly through the relational use of recognisable sources capable of evoking metaphorical, analogical, or eco-political associations – this has by no means excluded an ongoing engagement in the search for unfamiliar, non-referential sounds. Such a pursuit remains a fundamental impulse within the acousmatic tradition and continues to inform the creative approaches of many composers, including myself. In a recent article published in Revue Lien XI – ‘Expanding Semiotic Models for Sound Source Identification in Acousmatic Music’ – I reflected on this tension between reference and abstraction in my own music. Over the course of that investigation – and especially as theoretical questions around sonic referentiality began to take shape – a core question emerged: how might we generate acousmatic sounds – those that resist identification and evoke no immediate referent – acoustically, at the moment of capture, rather than relying on digital signal processing a posteriori?
One of the Sonoclisis project’s goals is to respond directly to that question. By exploring combinations of resonant bodies whose interactions produce spectrally complex and often unrecognisable results, the research can potentially offer an expansion of the field of acousmatic materials without defaulting to studio-based transformations.
As a byproduct of such a goal, this compositional strategy also aims to circumvent what Denis Smalley has called ‘technological listening’ – a mode in which recognition is not directed at the sound’s origin in the world, but at the technologies used to shape it. According to Professor Leigh Landy, with respect to such a listening mode:
listeners may focus on trying to puzzle out how an artist made something sound a certain way or, alternatively, may recognize the sound of a particular type of synthesis or preset from a synthesizer and lose his or her place in a piece. […] Here, specialized listeners pay attention to sound production, manipulation, and structuring techniques more than the sonic artwork itself, at least during periods of the work. (Landy 2007: 33)
This phenomenon, while analytically interesting, risks shifting the listener’s attention away from the musical discourse and toward the tools behind it. At the same time, it is precisely this kind of ambiguity – provoked by the sounds generated through Sonoclisis – that can make listeners, particularly specialists, curious about how those sounds were produced. In some cases, the absence of an identifiable source does not lead to abstraction, but rather to a heightened analytical attention focused on decoding the generative process behind the sound. While the project seeks to foreground the sonic outcome and its perceptual richness, it also acknowledges that the very qualities which make a sound compelling and referentially ambiguous may invite speculation about its origin. (Will it ever be possible to escape the scrutiny of a specialist listener?)
The research on Sonoclisis will, then, pursue a compositional path rooted in material experimentation, consistently guided by listening and compositional intent. It is committed to producing sounds that are referentially ambiguous – sounds that, while grounded in real physical interactions, resist immediate identification. At the same time, the research seeks to build knowledge about these processes, particularly by identifying combinations of sounding bodies that yield especially compelling or unexpected results. In this regard, we propose a research structure and an initial taxonomy of such combinations, as outlined in the next section.
2.5. Structure and preliminary Sonoclisis taxonomies
The future research in Sonoclisis is structured around eight core axes:
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(i) a bibliographic review aimed at conceptualising sound creation processes rooted in the interaction and coupling of vibrating bodies;
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(ii) the recording and cataloguing of sonic outcomes generated through such interactions – sourced both from the experimental repertoire of the 20th and 21st centuries and from newly devised combinations of resonant objects;
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(iii) the development of taxonomies based on modes of vibrational transfer, resonant properties of the interacting bodies, and excitation modalities – establishing classificatory frameworks that can support both analytical investigations and compositional applications.
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(iv) the analysis of the acoustic transformations emerging from these interactions, with a focus on understanding resonance behaviour and the mechanisms of energy exchange between coupled materials;
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(v) the algorithmic formalisation of the identified acoustic behaviour patterns within digital environments, enabling their implementation in physical modelling synthesis systems;
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(vi) a comparative study between the sounds resulting from direct material coupling (as in Sonoclisis) and those produced by the digital convolution of the corresponding spectral profiles;
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(vii) the composition of new works that incorporate the project’s findings, thereby establishing a compositional approach grounded in the principles of Sonoclisis;
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(viii) the Brazilian premiere of historically significant works aligned with the project’s thematic axis, fostering the dissemination and contextualisation of these practices within the local electroacoustic music landscape.
Beyond its contribution to sound research and compositional practices, the project aims to create a new corpus of references about Sonoclisis applied to musical creation, filling existing gaps in literature and in electroacoustic music practice. The results will be shared through concerts, publications, and materials that will be made available for composers and researchers for further investigation and musical creation.
We have begun to outline a preliminary taxonomy of the ways in which two or more sounding bodies may be subjected to Sonoclisis. The physical interaction between bodies can be categorised into two primary types: direct contact and indirect contact. (1) Direct contact may involve (1a) external coupling between the resonant surfaces of distinct bodies; (1b) internal insertion, where one object is placed inside another, thereby altering the latter’s internal structural properties and vibration behaviour. (2) Indirect contact can be further divided into (2a) fluid-mediated coupling, in which sound travels through a medium such as air or water, typically manifesting as sympathetic resonance; (2b) intermediated structural coupling, where a solid conductor (e.g., a string or metal rod) serves as a bridge between bodies; (2c) electroacoustic coupling, in which an electric signal transfers the vibration from one body to another. The latter may occur either: (i) directly, via transducers such as electromagnetic or piezoelectric actuators; or (ii) mediated through computation, where the signal is digitally transformed before being re-materialised into a second resonant object.
In addition, we are developing complementary taxonomies grounded in both the resonant properties of the materials involved and the modalities of excitation. The latter concerns whether one, both, or multiple bodies are externally excited, as well as the nature of that excitation – be it via mallets, friction, air pressure, or other means. The former addresses intrinsic physical characteristics of the interacting bodies, such as density, elasticity, and vibrational conductivity, all of which critically shape the resulting spectromorphological behaviour.
We strongly believe that the development of such taxonomies is essential for advancing the formalisation of physical modelling algorithms. By articulating how specific combinations of acoustic and physical properties lead to emergent sonic outcomes, this framework could inform future synthesis techniques capable of generating novel sonic materials grounded in the logic of Sonoclisis.
3. Final remarks
This ongoing research on Sonoclisis aims to provide a deeper understanding of the relationship between the physical coupling of sounding bodies and their resulting spectromorphology, with applications relevant not only to electroacoustic composition but also to instrumental music. The project seeks to assist both performers and composers by making available a comprehensive corpus of sounds and their comparative analyses, enabling composers to better anticipate the outcomes of their Sonoclisis-based explorations. Additionally, performers may use this knowledge to suggest substitutions of instruments or objects in a given context while preserving the intended sonic result.
We hope this article has provided a clear glimpse into the sound-based research currently underway at Studio PANaroma, and we welcome collaborations with researchers and institutions similarly engaged in exploring sonic material as a means of fostering contemporary composition and analysis.
