Optimal control theory : a method for the design of wind instruments

It has been asserted previously by the author that optimal control theory can be a valuable framework for theoretical studies about the shape that a wind instrument should have in order to satisfy some optimization criterion, inside a fairly general class. The purpose of the present work is to develop this new approach with a look at a specific criterion to be optimized. In this setting, the Webster horn equation is regarded as a controlled dynamical equation in the space variable. Pressure is the state, the control being made of two parts: one variable part, the inside diameter of the duct and one constant part, the weights of the elementary time-harmonic components of the velocity potential. Then one looks for a control that optimizes a criterion related to the definition of an {oscillation regime} as the cooperation of several natural modes of vibration with the excitation, the {playing frequency} being the one that maximizes the total generation of energy, as exposed by A.H. Benade, following H. Bouasse. At the same time the relevance of this criterion is questioned with the simulation results.Comment: To appear in Acta Acustica united with Acustica, 201

Reflections on Eight Years of Instrument Creation with Machine Learning

Machine learning (ML) has been used to create mappings for digital musical instruments for over twenty-five years, and numerous ML toolkits have been developed for the NIME community. However, little published work has studied how ML has been used in sustained instrument building and performance practices. This paper examines the experiences of instrument builder and performer Laetitia Sonami, who has been using ML to build and refine her Spring Spyre instrument since 2012. Using Sonami’s current practice as a case study, this paper explores the utility, opportunities, and challenges involved in using ML in practice over many years. This paper also reports the perspective of Rebecca Fiebrink, the creator of the Wekinator ML tool used by Sonami, revealing how her work with Sonami has led to changes to the software and to her teaching. This paper thus contributes a deeper understanding of the value of ML for NIME practitioners, and it can inform design considerations for future ML toolkits as well as NIME pedagogy. Further, it provides new perspectives on familiar NIME conversations about mapping strategies, expressivity, and control, informed by a dedicated practice over many years

Exploring the Digital Music Instrument Trombosonic with Extreme Users and at a Participatory Performance

We introduce the “Trombosonic” as a new digital music instrument inspired by the slide trombone. An ultrasonic sensor combined with a red laser allows the performer to play the instrument using similar movements to playing a trombone to change the pitch, despite the absence of a physical slider, by moving one hand back and forth. Additional sensors enhance the potential for musical expression by movement of the whole interface and by using the breath. We identify and discuss a variety of design issues arising from the Trombosonic. Due to its compact size and the lack of a slider, the Trombosonic can be played in many different ways. In order to explore varied potential uses of the Trombosonic, we carried out a series of informal evaluations. These included experts in new musical instruments, an older user, a younger user, an interaction design expert, and the audience at an experimental concert with audience participation. Future work is also discussed. Further technical development might include a built-in microphone to use the human voice and an expansion of the synthesiser’s features

Issues and techniques for collaborative music making on multi-touch surfaces

A range of systems exist for collaborative music making on multi-touch surfaces. Some of them have been highly successful, but currently there is no systematic way of designing them, to maximise collaboration for a particular user group. We are particularly interested in systems that will engage novices and experts. We designed a simple application in an initial attempt to clearly analyse some of the issues. Our application allows groups of users to express themselves in collaborative music making using pre-composed materials. User studies were video recorded and analysed using two techniques derived from Grounded Theory and Content Analysis. A questionnaire was also conducted and evaluated. Findings suggest that the application affords engaging interaction. Enhancements for collaborative music making on multi-touch surfaces are discussed. Finally, future work on the prototype is proposed to maximise engagement

Analyzing Visual Mappings of Traditional and Alternative Music Notation

In this paper, we postulate that combining the domains of information visualization and music studies paves the ground for a more structured analysis of the design space of music notation, enabling the creation of alternative music notations that are tailored to different users and their tasks. Hence, we discuss the instantiation of a design and visualization pipeline for music notation that follows a structured approach, based on the fundamental concepts of information and data visualization. This enables practitioners and researchers of digital humanities and information visualization, alike, to conceptualize, create, and analyze novel music notation methods. Based on the analysis of relevant stakeholders and their usage of music notation as a mean of communication, we identify a set of relevant features typically encoded in different annotations and encodings, as used by interpreters, performers, and readers of music. We analyze the visual mappings of musical dimensions for varying notation methods to highlight gaps and frequent usages of encodings, visual channels, and Gestalt laws. This detailed analysis leads us to the conclusion that such an under-researched area in information visualization holds the potential for fundamental research. This paper discusses possible research opportunities, open challenges, and arguments that can be pursued in the process of analyzing, improving, or rethinking existing music notation systems and techniques.Comment: 5 pages including references, 3rd Workshop on Visualization for the Digital Humanities, Vis4DH, IEEE Vis 201

Improvising with the threnoscope: integrating code, hardware, GUI, network, and graphic scores

Live coding emphasises improvisation. It is an art practice that merges the act of musical composition and performance into a public act of projected writing. This paper introduces the Threnoscope system, which includes a live coding micro-language for drone-based microtonal composition. The paper discusses the aims and objectives of the system, elucidates the design decisions, and introduces in particular the code score feature present in the Threnoscope. The code score is a novel element in the design of live coding systems allowing for improvisation through a graphic score, rendering a visual representation of past and future events in a real-time performance. The paper demonstrates how the system’s methods can be mapped ad hoc to GUI- or hardware-based control

Instructions not included: dementia-friendly approaches to DMI design

The development of bespoke musical tools such as many accessible digital musical instruments (ADMI) can neces- sitate specific design constraints. Within a field which of- ten promotes out of the box thinking and new interactions with experimental technologies, how do we design for user groups where these notions of interaction will be less famil- iar, and/or increasingly challenging due to the progression of cognitive decline? The relationship between age and the use of technol- ogy is understood within the wider context of human com- puter interaction (HCI), however, how this applies specifi- cally to musical interaction or contributes to a ‘dementia- friendly’ approach to digital musical instrument (DMI) de- sign is drastically underrepresented within the NIME com- munity. Following a scoping review of technology for arts activities designed for older adults with cognitive decline, we ran a series of involvement activities with a range of stakeholders living with, or caring for those living with de- mentia. Consolidating the knowledge and experience shared at these events, we propose five considerations for designing dementia-friendly digital musical instruments. We illustrate our approach with a range of new instruments co-designed to enable increased interaction with music for people living with dementia

The acoustic, the digital and the body: a survey on musical instruments

This paper reports on a survey conducted in the autumn of 2006 with the objective to understand people's relationship to their musical tools. The survey focused on the question of embodiment and its different modalities in the fields of acoustic and digital instruments. The questions of control, instrumental entropy, limitations and creativity were addressed in relation to people's activities of playing, creating or modifying their instruments. The approach used in the survey was phenomenological, i.e. we were concerned with the experience of playing, composing for and designing digital or acoustic instruments. At the time of analysis, we had 209 replies from musicians, composers, engineers, designers, artists and others interested in this topic. The survey was mainly aimed at instrumentalists and people who create their own instruments or compositions in flexible audio programming environments such as SuperCollider, Pure Data, ChucK, Max/MSP, CSound, etc