The creation of Composition Zeta (section three)
(available here in .pdf format)
As published in the Csound Journal – Summer 2001
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Since its inception, an important technical challenge of digital synthesis and computer music composition has involved creating complex and interesting sound evolutions and textures with minimal programming. A basic approach, when composing with Csound, has been to create a set of complex instruments that could be performed by a relatively simple score. Recently, I decided to take a different approach and try to compose an entire composition with only one, very simple, instrument. This article will describe the outcome. First let us examine the instrument. instr 1 kenv1 linseg ifreq * imod1, idur * .75, ifreq * imod2 a1 oscili iamp * .925, ifreq, ifn a2 butterbp a1, kenv1, 50 outs sqrt(kpan) * a3, (sqrt(1-kpan)) * a3 endin On its own, there is nothing earth shattering about this instrument. However, it gains a unique quality by the way it is treated in the score. instr start idur iamp ifreq kpan imod1 imod2 ifn i1 60 20 1000 150,000 0.5 0.01 50 1 Notice the frequency parameter of a1, ifreq(p5). Any time the value of p5 is less than 40hz or above 20,000hz (the approximate audible range of the human ear) so is the base frequency of a1. This serves two functions: With an orchestra of only fourteen very simple lines of code a composition of over twelve minutes in length was realized. There are many ways this orchestra could have been expanded to make it more complicated and more versatile. However, when composing one has to know when enough is enough. In this instance any more could have made the instrument unwieldy. Any less would have been too limited for it to provide the diversity needed to keep the listener’s interest for the entire composition. The diversity of sound obtained from this simple instrument illustrates the power of the Csound score. The layering of sound events and their slight offset in time as well as the various waveforms of the function tables are key to achieving the many textures. In the following section of the score, start times are offset by .05 seconds and the durations are 7 seconds. This adds depth and texture to this evolving set of sounds. Notice also the different frequencies of each event adding a density of timbre to the overall sound as well. f1 0 131073 10 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 1 0 1 instr start idur iamp ifreq kpan imod1 imod2 ifn i1 424 7 1000 300 0.5 1 100 4 While composing a complex score it is easy to become overwhelmed by a lengthy bit of code. This score is over 2700 lines long. I find it very useful to employ a powerful spreadsheet program (such as MS Excel) for streamlining and organizing the production of such a score. There are many good reasons for this, here are a just a few:
Here is the complete .sco and .orc for Composition Zeta (section three), one section of a larger work. (Warning! Even on a fast computer, compile times are lengthy.) Listen for the diversity of sound and texture. Did one simple instrument "carry" the entire composition? Drop me an e-mail and let me know what you think. There is much to be said in favor of simple instruments and complex scores. One does not have to be an expert with code, math, digital synthesis or even Csound to create interesting compositions utilizing Csound. With a little imagination, creativity, and unconventional thinking, a simple instrument can yield amazing results. Thank you for your attention. |