John Bischoff Source: Leonardo Music Journal, Vol
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Software as Sculpture: Creating Music from the Ground up Author(s): John Bischoff Source: Leonardo Music Journal, Vol. 1, No. 1, (1991), pp. 37-40 Published by: The MIT Press Stable URL: http://www.jstor.org/stable/1513119 Accessed: 23/07/2008 16:30 Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at http://www.jstor.org/page/info/about/policies/terms.jsp. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the JSTOR archive only for your personal, non-commercial use. Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained at http://www.jstor.org/action/showPublisher?publisherCode=mitpress. Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. JSTOR is a not-for-profit organization founded in 1995 to build trusted digital archives for scholarship. We work with the scholarly community to preserve their work and the materials they rely upon, and to build a common research platform that promotes the discovery and use of these resources. For more information about JSTOR, please contact [email protected]. http://www.jstor.org ARTIST'S ARTICLE Software as Sculpture: Creating Music from the Ground Up John Bischoff his article discusses two compositions that I around 1976. The KIM-1was a composed by writing software for small computer-music single board system designed systems. Both pieces are entirely electronic. All sounds are around a 6502 central processing synthesized or triggered by the computer program, which is unit (CPU) with a built-in key- ABSTRACT partially guided by a human performer. The process by pad and 6-digit light-emitting which these pieces were constructed is characterized by diode (LED) display [2]. Ger- Theauthor discusses two elec- bottom-up design and the empirical method. Starting from ald Mueller, of the Electronic tronicmusic compositions that to an initial idea or perception, I composed each piece by Music Lab at City College of San typifyhis approach composing withsmall a feature at a time, aesthetic choices Francisco,also me with computer-musicsys- adding making by provided tems.The author's compositional As a result of this some to repeated close listening. process, early opportunities program techniqueis characterized bybot- features were refined, others were dropped. Finally, the in assembly language. After buy- tom-upsoftware design and close identity of each piece emerged. Although this way of work- ing my own KIM, I started writ- attentionto emergingdetails of the medium.These methods within a medium is common in visual art, it is unusual ing programs in 6502 machine computer ing resultin a of within the field of It is code both to make solo sculpturalprocess computer programming. generally pieces compositionthat is uniquein the in thought that programmers implement their ideas on the and eventually to play com- fieldof computermusic. Some of computer with as few unforeseen developments as possible, puter-network bands with Hor- thedetails of this process are out- and that ideas flow in only one direction, from the operator ton and others [3]. In this article, linedand distinctive features of the musicare discussed. to the machine. From the vantage point of an artist, though, I will focus on two examples of see the flow in the direc- solo both of it is just as easy to going opposite my computer work, m tion: the medium reveals itself as the artist proceeds, and which were also adapted for use such revelations shape the direction in which the artist in network bands at one time or continues. This interaction between artist and medium, and another. the intimacy it suggests, is no different for a computer artist. In programming a computer to generate music, distinc- tive characteristics and limitations of the computer medium AUDIO WAVE are inevitably revealed in the sonic behavior of the program. These characteristics might include timing complexities, I composed Audio Wave (1978-1980) [4] for pianist Rae effects created by sudden transitions in loudness or pitch, Imamura; she first performed the piece at 1750 Arch Street, or unforeseen artifacts that are the result of the unique flow Berkeley, on 30 May 1980. I wanted to create a live computer of the program. As these features arise and become part of piece in which both of Imamura's hands would continually the musical process, the composer/programmer is brought activate computer keypads instead of piano keys. I wanted into contact with the fundamental nature of the computer her actions to influence an ongoing musical output pro- as a musical instrument. duced by a computer rather than to initiate each sound as I began using computers to make electronic music in would be the case with a piano. To this end, I extensively 1977. Prior to that time, I had composed electronic pieces modified an earlier random-tone-generating program that using analog synthesizers, tape recorders and custom-built I had written for the KIM,ran it simultaneously on two KIMs, circuits designed for particular musical functions. Often the and made its behavior partially controllable by pressing keys sonic character of a synthesizer patch or a custom circuit on the KIM keypads. defined the structure of a piece. For example, the piece The final version of the program, written in 6502 machine Piano Socialemployed multiple recorded sounds fed into a code, generates an 8-bit sonic output characterized by a configuration of switching circuits (designed by Paul De- continuous stream of highly modulated tones. Each tone marinis) such that the presence of one sound would trigger starts as a simple ramp, triangle or random waveshape built the occurrence of another. The action of the switching up in memory in a wave table. At each audio cycle output, circuits highlighted details in the recorded sound in a way the waveshape is modified according to the following scheme: that would not be possible in a purely acoustic medium. This the value at a current point in the wave table is altered a focus on the material nature of the medium is also typical number of steps toward a maximum or minimum and the of much of my work with computers [ 1]. current point itself is moved a number of steps toward the My introduction to computers came about primarily Bischoff educator), 1374 Francisco St., (A 94702, U.S.A. association with Horton, an John (composer, Berkeley, through my James experimental- Received 10 October 1990. music composer and theorist based in the San Francisco Bay Manuscript solicited by Larry Polansky. Area, who introduced me to the KIM-1 microcomputer ? 1991 ISAST Pergamon Press plc. Printedin Great Britain. 0961-1215/91 $3.00+0.00 LEONARDO MIUSICJOURNAL,Vol. 1, No. 1, pp. 37-40, 1991 37 Fig. 1. Waveform modulation in Audio Wave. (a) An idealized superimposition of multiple waveforms, which are the result of approximately 80 cycles of modification carried out on a single ramp wave; (b) several typical waveforms extracted from (a). beginning or end of the table. The re- insertion of 'key' functions into the flow tronic compensations for the absence sult after many audio cycles is a continu- of the program. The execution of a of musical phenomena found in acous- ally changing waveshape that waffles 'key' function is triggered when the tic instruments: around a given area of points in a re- performer depresses KIM keypads to *The onset of an acoustic tone, with peating modulation pattern (Fig. 1). influence the musical output of the pro- its characteristic richness and com- This technique creates tones with over- gram. The additional execution time plexity, is missing in Audio Wave tone spectra that expand and contract to required to process a 'key'function drops and is made up for by modulation varying degrees at varying rates. the pitch of the sounding tone notice- of the electronic tone throughout An additional timbraleffect arisesfrom ably. I retained this feature for its its length. It is as though the usual what might be considered a defect in mechanical quality: through it, one can richness at the start of each tone is my design: many program functions, visualizethe performer'skeystrokes shap- now spread out in time over its du- including keypad scanning, wave mod- ing the sonic output overall as well ration. Without the beginning, mid- ification, general housekeeping, are pro- as leaving a mechanical impression on dle and end of the acoustic envelope, grammed within the main audio loop the course of each tone. The 16 key- tones switch from one to another to at the end of each waveform cycle. function commands for each KIM form one continuous ribbon. The Before going to output the next wave- include sustain current tone, change bending and warping of that rib- form, the program executes these func- tempo, contract pitch range, repeat last bon are highlighted in Audio Wave. tions and therefore a flat portion is intro- 3 events and switch starting waveform. *The age-old magic of an acoustic duced into the waveshapebetween cycles The overall sonic effect of Audio Wave sound being struck into being by a (see Fig. 1). This 'dead zone' in each is one of unconstrained electronicism, human agent is replaced by the surg- audio cycle fluctuates in length due to an embracing of the electronic medium ing potential of a waffling speaker. the varying number of functions that in its power to create a new voice.