Computer Sound Design Titles in the Series Acoustics and Psychoacoustics, 2nd edition (with website) David M. Howard and James Angus The Audio Workstation Handbook Francis Rumsey Composing Music with Computers (with CD-ROM) Eduardo Reck Miranda Digital Audio CD and Resource Pack Markus Erne (Digital Audio CD also available separately) Digital Sound Processing for Music and Multimedia (with website) Ross Kirk and Andy Hunt MIDI Systems and Control, 2nd edition Francis Rumsey Network Technology for Digital Audio Andrew Bailey Computer Sound Design: Synthesis techniques and programming, 2nd edition (with CD-ROM) Eduardo Reck Miranda Sound and Recording: An introduction, 4th edition Francis Rumsey and Tim McCormick Sound Synthesis and Sampling Martin Russ Sound Synthesis and Sampling CD-ROM Martin Russ Spatial Audio Francis Rumsey Computer Sound Design Synthesis techniques and programming Second edition Eduardo Reck Miranda Focal Press An imprint of Elsevier Science Linacre House, Jordan Hill, Oxford OX2 8DP 225 Wildwood Avenue, Woburn MA 01801-2041 First published as Computer Sound Synthesis for the Electronic Musician 1998 Second edition 2002 Copyright © 1998, 2002, Eduardo Reck Miranda. All rights reserved The right of Eduardo Reck Miranda to be identified as the author of this work has been asserted in accordance with the Copyright, Designs and Patents Act 1988 No part of this publication may be reproduced in any material form (including photocopying or storing in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright holder except in accordance with the provisions of the Copyright, Designs and Patents Act 1988 or under the terms of a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London, England W1T 4LP. Applications for the copyright holder’s written permission to reproduce any part of this publication should be addressed to the publisher British Library Cataloguing in Publication Data Miranda, Eduardo Reck, 1963– Computer sound design: synthesis techniques and programming. – 2nd ed. – (Music technology series) 1. Computer sound processing 2. Music – Data processing I. Title II. Computer sound synthesis for the electronic musician 786.7Ј6 Library of Congress Cataloguing in Publication Data A catalogue record for this book is available from the Library of Congress ISBN 0 240 51693 1 For information on all Focal Press publications visit our website at: www.focalpress.com Composition by Genesis Typesetting, Rochester, Kent Printed and bound in Great Britain Contents Series introduction ix Foreword by Jean-Claude Risset xi Preface xv 1 Computer sound synthesis fundamentals 1 1.1 Digital representation of sound 1 1.2 Basics of computer programming for sound synthesis 8 2 Loose modelling approaches: from modulation and waveshaping to Walsh and wavetable 19 2.1 Amplitude modulation 20 2.2 Frequency modulation 23 2.3 Waveshaping synthesis 38 2.4 Walsh synthesis 41 2.5 Binary instruction 43 2.6 Wavetable synthesis 43 3 Spectrum modelling approaches: from additive to analysis–resynthesis and formant 49 3.1 Additive synthesis 50 3.2 An introduction to spectrum analysis 51 3.3 Analysis and resynthesis 57 3.4 Formant synthesis 66 4 Source modelling approach: from subtractive and waveguides to physical and modal 69 4.1 Subtractive synthesis 71 4.2 Waveguide filtering 75 4.3 Karplus–Strong synthesis 77 v Contents 4.4 Cellular automata lookup table 78 4.5 Physical modelling 80 4.6 Modal synthesis 97 5 Time-based approaches: from granular and pulsar to PSOLA and statistical 100 5.1 Granular synthesis 101 5.2 Pulsar synthesis 111 5.3 Resynthesis by fragmentation and growth 113 5.4 Waveset distortion 117 5.5 PSOLA 118 5.6 Statistical wavecycle synthesis 119 5.7 Sequential waveform composition 121 6 Practical case studies and sound design secrets: from humanoid singing to Klingon phasers 125 6.1 Associating cause and effect 126 6.2 Synthesising human vocal sounds using subtractive synthesis 128 6.3 Physical modelling synthesis of the human voice 137 6.4 Towards a framework for sound design using granular synthesis 152 7 Towards the cutting edge: artificial intelligence, supercomputing and evolutionary systems 157 7.1 Artificial intelligence sound synthesis 157 7.2 Supercomputing and sound synthesis 172 7.3 Evolutionary sound synthesis 182 8 Introduction to the software on the accompanying CD-ROM 193 8.1 pcmusic 193 8.2 Nyquist 197 8.3 Som-A 201 8.4 Audio Architect 203 8.5 Reaktor 206 8.6 NI-Spektral Delay 207 8.7 Praat 208 8.8 Reality 211 8.9 Diphone 213 8.10 The CDP sound transformation toolkit 215 8.11 Sound Shaper 217 8.12 LASy 218 8.13 Wigout and TrikTraks 220 8.14 SMS 222 8.15 Chaosynth 224 8.16 Pulsar Generator 226 8.17 Koblo Vibra 1000 227 8.18 crusherX-Live 228 8.19 Virtual Waves 229 vi Contents Appendix 1: Mathematical specifications 233 Appendix 2: Formant values 240 Appendix 3: Artist’s Inductive Machine Learning Algorithm 242 References 245 CD-ROM instructions 249 Index 257 vii This Page Intentionally Left Blank Series introduction The Focal Press Music Technology Series is intended to fill a growing need for authoritative books to support college and university courses in music technology, sound recording, multimedia and their related fields. The books will also be of value to professionals already working in these areas and who want either to update their knowledge or to familiarise themselves with topics that have not been part of their mainstream occupations. Information technology and digital systems are now widely used in the production of sound and in the composition of music for a wide range of end uses. Those working in these fields need to understand the principles of sound, musical acoustics, sound synthesis, digital audio, video and computer systems. This is a tall order, but people with this breadth of knowledge are increasingly sought after by employers. The series will explain the technology and techniques in a manner which is both readable and factually concise, avoiding the chattiness, informality and technical woolliness of many books on music technology. The authors are all experts in their fields and many come from teaching and research backgrounds. Dr Francis Rumsey Series Consultant ix This Page Intentionally Left Blank Foreword By Jean-Claude Risset The book Computer Sound Design: Synthesis techniques and programming by Eduardo Reck Miranda is most welcome – it should be very helpful to anyone concerned with music technology. During the last century, electricity has gradually permeated the world of sound. Most music is now heard through loudspeakers. But, beyond reproduction, electrical technology has also brought radically new resources for the production of new sounds and music. It took time for the musical world to become aware of the potential of these resources. Yet, for many years, Edgard Var`ese tried to persuade researchers and institutions to take advantage of science and technology for developing sound producing machines – only at the end of his life was he able to compose tape music and encourage the first steps of computer music. Iannis Xenakis called upon the resources of the computer for several of his compositions and Pierre Boulez initiated IRCAM, an institute dedicated to musical research and creation and which mostly uses digital tools. Popular music could never have evolved as it has done without electronic equipment and the quest of groups for developing their own ‘sound’ involves research into sound design. Thus the new possibilities have already had a far-reaching influence on music composition. The exploration of these novel possibilities is still going on: it is the most exciting challenge for musicians today. Advanced electronic technology for sound has long been ‘analogue’; it has opened new possibilities – ‘musique concr`ete’, made up from recorded acoustic sounds, and ‘electronic music’, resorting to sounds produced electronically. However, mastering analogue technol- ogy demanded artful wizardry, so musicians generally used ready-made possibilities rather than developing their own. Moreover the equipment tended to be unstable and drifting, and it rapidly became obsolete. Since the late 1950s, digital technology of sound, introduced by Max Mathews, has gradually replaced analogue technology. Digital coding brings precision, stability and reproducibility xi Foreword to sound synthesis and processing, and it allows sound control to benefit from the boundless possibilities of the general-purpose computer. As François Bayle often says, the computer is not a tool, it is rather akin to a workshop – everyone can mould it to define one’s own world, to design one’s own timbres, to build one’s own tools, both intellectual and material, shaped according to the individual’s inclinations. What is at stake here is very important – the digital domain permits the choice of specific constraints and the extension of compositional control to the level of the sound itself, not merely composing with sounds, but composing the sounds themselves. With digital technology, a promising and unbound world of new sonic and musical possibilities appears within reach. However, this world must be explored. I myself have been so attracted to it that I have spent a great deal of my time in this exploration. John Chowning had the same inclination and he not only developed a powerful new method for sound synthesis (i.e. FM), but also created new and convincing musical works, and fostered our understanding of musical sound and its perception. However exciting, this phase of exploration was demanding, and many musicians were unwilling to devote much time to exploring and developing new possibilities. Although powerful, synthesis software was somewhat hard to use on large computers, which were not very user-friendly. When digital real-time sound systems appeared about 25 years ago, many musicians thought they could use real-time controls, their ear and intuition to choose empirically among the possibilities offered for sound.