Teaching rule‐based algorithmic composition: the PWGL library cluster rules

This paper presents software suitable for undergraduate students to implement computer programs that compose music. The software offers a low floor (students easily get started) but also a high ceiling (complex compositional theories can be modelled). Our students are particularly interested in tonal music: such aesthetic preferences are supported, without stylistically restricting users of the software. We use a rule‐based approach (constraint programming) to allow for great flexibility. Our software Cluster Rules implements a collection of compositional rules on rhythm, harmony, melody, and counterpoint for the new music constraint system Cluster Engine by Örjan Sandred. The software offers a low floor by observing several guidelines. The programming environment uses visual programming (Cluster Rules and Cluster Engine extend the algorithmic composition system PWGL). Further, music theory definitions follow a template, so students can learn from examples how to create their own definitions. Finally, students are offered a collection of predefined rules, which they can freely combine in their own definitions. Music Technology students, including students without any prior computer programming experience, have successfully used the software. Students used the musical results of their computer programs to create original compositions. The software is also interesting for postgraduate students, composers and researchers. Complex polyphonic constraint problems are supported (high ceiling). Users can freely define their own rules and combine them with predefined rules. Also, Cluster Engine’s efficient search algorithm makes advanced problems solvable in practice

Analysing the Creative Process through a Modelling of Tools and Methods for Composition in Hans Tutschku’s Entwurzelt

The analysis of the creative processes involved in electroacoustic music may to a large extent rely on the thorough study of the technological tools used for the realisation of a musical work, both on the composition and on the performance sides. Understanding the behaviour and potential range of aesthetic results of such tools enables the musicologist to approach the studied work much beyond its final form, as presented on tape or as performed on a particular occasion: gaining knowledge on a wider technological context leads to considering the actual artistic decisions in the perspective of the potential outcomes that the composer and performer could face but not necessarily adopt. Hence, analysing an electroacoustic work on the basis of the study of its creative context, technological tools and compositional methods may constitute a useful approach to a better understanding of its related creative processes. However, the implementation of such an approach, mainly based on the hardware or software elements used during the creation of a given work, is not straightforward. First, it implies that the considered technologies are still in use and have not be come irreversibly obsolete. In this matter, new performances of a work are good opportunities for such investigations, as they often provide a technical update and require a deep understanding of the composer’s intentions. The musicologist also needs to have access to the resources, which may not be available without a direct contact with the composer. Assuming these conditions are reached,the musicological and organological studies can encounter another issue, particularly in the digital domain: the sources are not always presented under forms that are directly readable by the analyst, for instance with a specific programming language. Despite all these possible difficulties, many cases of technological tools lean themselves to an in-depth investigation, leading to relevant conclusions on some of the creative processes appearing in the field of electroacoustic music. In the context of a common session of several analytical approaches to a same electroacoustic piece, Hans Tutschku’s Entwurzelt for six singers and electronics (2012), this article focuses on the investigation and modelling of tools and methods of the compositional stage of the realisation of the work. During a performance of Entwurzelt, the electronic materials are simply triggered as events by one of the singers, without further interactivity–thus, the essential part of the research on the electroacoustic realisation aims at exploring the processes used during the compositional stage itself. As the electronics are used as an extension of the live vocal expression by the means of harmonic amplification and complex texturing, the tools for generation and processing of both symbolic representations and audio explored. Since the software tools that constitute the primary sources for our research were not directly designed to be used beyond their creative purposes, this talk presents software modelling implemented by the two authors to demonstrate the technological context in which Tutschku could compose Entwurzelt, emphasizing his creative methods and the decisions he could make upon a wider range of possible materials and processing techniques

Real-time Analysis of Interactive Scores in PWGL

In this article, we introduce an original approach to computerized music analysis within the graphical computer-assisted composition environment called PWGL. Our aim is to facilitate real-time analysis of interactive scores written in common Western music notation. To this end, we have developed a novel library that allows us to analyze scores realized with the help of ENP, and to visualize the results of the analysis in real-time. ENP is the native music notation tool of PWGL able to produce automatically typeset and interactive music notation. Here, it is extended to support the display of analytical information that can be drawn on top of the score as an overlay. The analysis backend is realized with the help of our built-in musical scripting language. The language is based on pattern-matching and allows for a rich access of score information. The results of the analysis are presented directly as a part of the original score leveraging the extensible and interactive visualization capabilities of ENP

Compositions created with constraint programming

This chapter surveys music constraint programming systems, and how composers have used them. The chapter motivates and explains how users of such systems describe intended musical results with constraints. This approach to algorithmic composition is similar to the way declarative and modular compositional rules have successfully been used in music theory for centuries as a device to describe composition techniques. In a systematic overview, this survey highlights the respective strengths of different approaches and systems from a composer's point of view, complementing other more technical surveys of this field. This text describes the music constraint systems PMC, Score-PMC, PWMC (and its successor Cluster Engine), Strasheela and Orchidée -- most are libraries of the composition systems PWGL or OpenMusic. These systems are shown in action by discussing the composition process of specific works by Jacopo Baboni-Schilingi, Magnus Lindberg, Örjan Sandred, Torsten Anders, Johannes Kretz and Jonathan Harvey

George Perle’s Twelve–Tone Tonality: some developments for CAC using PWGL

This paper presents a description and some developments on Perle’s theory and compositional system known as Twelve-Tone Tonality, a system that, because of its characteristics and fundamentals, is currently associated with Schoenberg dodecaphonic system. Some research has been made in the last few decades in order to develop his model in a Computer Assisted Composition (CAC) environment. After some efforts in order to analyse these prototypes, we realize that in general they were discontinued or outdated. A three-scope proposal is so outlined: Firstly, to simplify the grasp of a system that presents an easily understandable starting premise but afterwards enters a world of unending lists and arrays of letters and numbers; Secondly, to present the implementation process already started using PWGL [1] (see Laurson, 1996; Laurson, 2003; Laurson, 2009). Finally, the model is applied in a short original compositional work, and it is presented and analysed emphasizing the standpoints properties of the system. Some further considerations were made regarding the continuity of this project where the construction of a dedicated PWGL library of Perle’s model reveals a pre-compositional necessary tool. PWGL software was selected due to its specific fitting features: it is based on Common Lisp - perfectly powerful and suitable to process lists of integers — and it is specialized in CAC

Compositions created with constraint programming

This chapter surveys music constraint programming systems, and how composers have used them. The chapter motivates and explains how users of such systems describe intended musical results with constraints. This approach to algorithmic composition is similar to the way declarative and modular compositional rules have successfully been used in music theory for centuries as a device to describe composition techniques. In a systematic overview, this survey highlights the respective strengths of different approaches and systems from a composer's point of view, complementing other more technical surveys of this field. This text describes the music constraint systems PMC, Score-PMC, PWMC (and its successor Cluster Engine), Strasheela and Orchidée -- most are libraries of the composition systems PWGL or OpenMusic. These systems are shown in action by discussing the composition process of specific works by Jacopo Baboni-Schilingi, Magnus Lindberg, Örjan Sandred, Torsten Anders, Johannes Kretz and Jonathan Harvey

The language of the assistant and the language of the creator : selected aspects of computer assisted composition

This paper is concerned with the creative process involved in making a "computer assisted composition". It follows the relationship to the technologies used, from the point of view of the communication between composer and electronic machine. It offers a perspective on the relation between the act of "programming" and the act of "composing". From this point of view, it compares the current state of the creative process with the situation at the time of the first computer-assisted realizations

Score Playback Devices in PWGL

(Abstract to follow

Programming in style with bach

ISBN 979-10-97-498-01-6. A post-proceeding version is planed at LNCS Springer. The proceedings are available at URL: https://cmmr2019.prism.cnrs.fr/Docs/Proceedings_CMMR2019.pdfInternational audienceDifferent programming systems for computer music are based upon seemingly similar, but profoundly different, programming paradigms. In this paper, we shall discuss some of them, with particular reference to computer-aided composition systems and Max. We shall subsequently show how the bach library can support different programming styles within Max, improving the expression, the readability and the maintainance of complex algorithms. In particular, the forthcoming version of bach introduces bell, a small textual programming language embedded in Max and specifically designed to facilite programming tasks related to manipulation of symbolic musical material