Starting in the early 1960s Karlheinz Stockhausen composed several instrumental works which he called "process compositions". These did away with traditional stave notation and instead used symbols including plus, minus, and equal signs that indicated the successive transformations of sounds that were otherwise unspecified or unforeseeable by the composer. In this way he brings elements of improvisation into the fold of Western classical music where the strict adherence to a fixed score left little room for interpretation by musicians. The scores in his process pieces don’t dictate specific notes or ways of playing but rather specify the way a sound is to be changed or imitated. Taking a cue from his studies of information theory Stockhausen created a way of writing music that is similar to computer programming. The program “determines the way information is processed while leaving the choice of information to be processed to the individual user.” (Maconie 1990, 156-157)
Stockhausen’s process pieces include Plus-Minus (1963), Prozession (1967), Kurzwellen, and Spiral (both 1968). Eventually they led to the text based processes of his intuitive music compositions in the cycles Aus den sieben Tagen (1968) and Für kommende Zeiten (1968–70).
Kurzwellen (Short waves), the third of the process pieces also marks the beginning of Stockhausen’s magnificent voyage using shortwave receivers as a medium for musical transportation. The formal procedures in Kurzwellen (and the others) are fixed. Stockhausen thinks of these not as fixed in the way Beethoven’s Fifth symphony is a fixed piece that will sound the same to a greater or larger degree from recording to recording or performance to performance. Only the processes themselves are fixed. These are indicated primarily by plus, minus, and equal signs and constitute the composition.
Yet the sound materials themselves, like the knobs on the tuners, are variable. The process scores can be followed and bring about very different results each time they are played and yet somehow still sound similar. The sound material coming in from the shortwave radios is unpredictable. Yet the prescribed processes themselves can be heard from one performance to another as being "the same". These developments in musical theory and practice make live performances and new recordings exciting events.
The sounds coming in from the radio are what they players use as source material for the process of transformation as indicated by the score. Each player has a radio at their station. Stockhausen writes, “An undreamed intensity of listening and of intuitive playing is reached – and shared by all co-players and listeners – through the concentration of all players on unforseeable events coming from the realm of short-waves, in which one only very rarely knows who composed or produced them, how they came into being or from where, and in which all possible acoustic phenomena can appear.”
In practice the performers search for desirable sounds on the radio. These are for the most part the more abstract and noisy sounds found in the spectrum. Then they replicate those sounds on their instruments and transform them by using variations in register, volume, duration or rhythmic density. There are additional instructions in the score for players to form synchronous duo, trio and quartet events, where players play together in tandem, or alternatively trade short events with one another.
Part of the reason Stockhausen proscribed shortwave receivers rather than just the AM and FM broadcast band receivers most often used by John Cage is that they pulled in sounds from around the world. This played into his idea of creating a kind of world music. Shortwave also has a rich variety of sounds that allows the musicians greater freedom in finding sound material transform.
He continued to use shortwave radios in the pieces Spiral, Pole for 2, and Expo for 3. Writing of Spiral the composer says, "Doesn't almost everyone own a short-wave receiver? And doesn't everyone have a voice? Wouldn't it be an artful way of life for everyone, to transform the unexpected (which one can receive on a short-wave radio) into new music - i.e. into a consciously-formed sound process which awakens all intuitive, mental, sensitive and artistic faculties, and makes them become creative, so that this awareness and these faculties rise like a spiral?!"
Expo is kind of the penultimate of these pieces, though it shares close similarities with Spiral and Pole, differing mostly in the number of players. All can be heard as being part of the same family of process pieces using shortwave radio. Expo was written for Stockhausen's 1970 stay in Japan at the World Fair in Osaka ("EXPO '70"). For the Fair Stockhausen designed a large spherical auditorium that was then developed by his collaborator Fritz Bornemann. Outfitted with 50 loudspeakers the audience was literally surrounded on all sides by sound. Karlheinz was able to control the movement of the sound mix around these speakers, moving the audio vertically and horizontally. Sometimes he created rising and falling spiral motions using what was termed a "rotation mill". There were also various balcony stages and platforms as the podium that gave the works peformed there further spatial dimension. For 183 his crew of twenty performed daily from 3:30 to 9pm. With breaks for individual musicians I’m guessing. The German pavilion became one of the main attractions at Expo '70.
These pieces represent a kind of music where both musicians and listeners must surrender completely to the process without worrying about the outcome. As humans this “not worrying about the outcome” of an action or a path taken can be a brutal challenge. These works embody a philosophy that has the effect of helping me to worry less about outcomes in my life. Process music as applied to my life gives me a sense of freedom from the outcome of an action. This allows me to be more present with the action itself as it happens, whether it is writing, radio, or some other activity. Listening to process music reminds me that I need to surrender to what I am doing in the moment. Surrender is difficult. Part of the joy to be found in the arts is submitting to how they grasp hold of us. Listening itself becomes a transformation.
To the amateur radio or SWLing enthusiast the sounds of Kurzwellen will be familiar. The static crashes and buzzes, warbling of telemetry, announcers in multiple languages and mysterious numbers stations are sweet nectars of sound for the radio hobbyist. Listening to these recordings is like drinking a fine wine. I prefer it served in a darkened room with ears open to the world.
http://stockhausenspace.blogspot.com/ (plus/minus series of articles)
The works of Karlheinz Stockhausen, by Robin Maconie, 2nd edition.