"The Byte Book of Computer Music" Edited by Christopher P. Morgan Copyright 1979 ISBN: 0-931718-11-2 Review, "Computer Music Journal," 1980, Vol. 4, No. 1 (Spring, 1980), pg. 82-84. Review by Robert Poor Contrary to popular example, viable computer music systems need not be complex nor expensive. Computer music should be available to the masses. BYTE magazine has a reputation for supporting the basic precepts of simple and accessible computer projects. Therefore I was excited at the prospect of reviewing "The BYTE Book of Computer Music." The book is a collection of articles from past issues of BYTE, along with some new material. The first two articles of the book, "SCORTOS: Implementation of a Music Language" by Hal Taylor, and "A Two Computer Music System" by Jeffery H. Lederer, Toni Dwyer, and Margot Critchfield, describe systems for editing and performing musical scores on microprocessor systems. Both systems described have a simple scoring language dedicated toward polyphonic tonal music. Both systems also have the ability to perform compositions on their respective output devices, which are some sort of keyboard device. Hal Taylor's "SCORTOS" is set up to drive any keyboard device that has a relay driver board interfaced to it. The Project Solo system ("A Two Computer Music System") is tied to a small pipe organ. Lederer, Dwyer, and Critchfield describe the evolution of their project, which turns out to be a good example of synthesis. It is cheerfully written and fun to read. Jef Raskin's "The Microcomputer and the Pipe Organ" highlights Jef's now-famous pipe organ, and demonstrates some elegantly radical approaches to a variety of design problems. As for "Tune In With Some Chips" by Ted Sierad, "A $19 Music Interface" by Bill Struve, and "Simple Approaches to Computer Music Synthesis" by Thomas G. Schneider, each of these articles describes an interface, designed to generate square waves at a frequency specified by a microprocessor. Of the three, Struve's "$19 Music Interface" is the best. His circuit can play four different notes at once and is cheaper than either of the others. His section on "Music Theory for Computer Nuts" provides some valuable information on the matter of tuning and temperament, an important topic that would otherwise be completely overlooked. "A Sampling of Techniques For Computer Performance of Music" by Hal Chamberlin is a good overview article. Read it if you haven't been initiated to such rubric as "Nyquist frequency," "aliasing." "quantizing noise." I have long respected Mr. Chamberlin's talent for explaining electronics to amateurs, and I am glad to see him spreading the word about computer music. Chamberlin also presents many specific techniques and circuits for microprocessors and digital synthesis, and thus does the computer music community a great service. If it weren't for this article, a reader might get the impression that all microprocessor-generated music is made up of single-voice square waves. Chamberlin saves the day by describing how to build a simple but adequate 8-bit DAC for microprocessors. Additive synthesis using Walsh Functions, as described in "Walsh Functions" by Benjamin Jacoby, sounds like a good idea at first. Unfortunately (as the article points out), Walsh functions are a pain to work with, mathematically and electrically, and therefore haven't gained much acceptance in computer music. The articles "Notes on Anatomy: The Piano's Reproductive System" by Chris Morgan, and "Interfacing Pneumatic Player Pianos" by Carl Helmers deal with Colin Nancarrow's instrument of choice: the player piano. Morgan's "Notes on Anatomy" doesn't mention computers at all, but provides a useful introduction to player pianos. Helmers's "Interfacing Pneumatic Player Pianos" is a practical "here's how I did it" article. After reading "Electronic Organ Chips For Use in Computer Music Synthesis" by Robert Grappel, I really don't feel the need for the choice between a Fox Trot and a Mambo automatic rhythm machine in my computer music system. However, maybe somebody out there does. The Fourier Transform is a powerful analysis tool for computer music. It is described in "Fast Fourier Transforms On Your Home Computer" by William D. Stanley and Steven J. Peterson, and "Fast Fourier Transforms For the 6800" by Richard Lord. In theory, you can use it to discover the spectral characteristics of any musical instrument, and use this information in the synthesis of new sounds. However, to get musically meaningful results, you must analyze reasonably large quantities of data. Unfortunately, the programs described in both articles handle only 256 samples of data, which is probably not enough to be of much use, though they could both be modified to handle more. "Polyphony Made Easy" by Steven K. Roberts describes a way to interface an organ keyboard to a microprocessor. It is encouraging to see that someone is thinking about musical input devices. However, it is possible the circuit presented is too complex to justify the results. Although the basic idea behind the interface is a good one, calculation shows that the same functionality could be achieved with a much simpler interface. Both of the articles, "Music From The Altair 8800 Computer" by Loring C. White and "Teach KIM To Sing" by Peter H. Meyers are examples of "what you can do with almost nothing," in which a speaker is connected to a microprocessor in the simplest possible means (via an interrupt bit or an IO port). You can then program your micro to make square waves through the speaker. It isn't music yet, but it's a start, and it's easy. "A Terrain Reader" by Rich Gold is my favorite article in the book. Gold describes the system he used in a piece for musical theater performed at Mills College. His system wins my praise for several reasons. First, it uses a real D to A converter. This is already a vast improvement over the typical "square- wave syndrome" that seems to prevail in these circles. Second, it demonstrates the use of a computer in the compositional process. High-level structures (in this case, a conceptual "terrain") work to define the actual sound of the music. Third, it describes an interactive system, where the microprocessor system becomes a real "live instrument." This article describes microprocessor music as it really should be. Though The BYTE Book of Computer Music covers several topics thoroughly, there are some important subjects left unexplored. For example, beginners in the field would benefit from a more in-depth treatment of digital signal processing theory and technique. There should be more attention given to the interactive performance of music and the problems of human interface (How do you communicate with your synthesizer?). And is it true that nobody is writing music on microcomputers using any kind of high-level music language? It seems that computers, the great problem-solving devices, have demonstrated an even greater potential as problem creating devices. But that's exactly what makes them fun. - Reviewed by Robert Poor CCRMA Stanford University Stanford, California