alien to music—technical, social, and non-musical aesthetic contexts—which are decisive for the conception of the works in which the graphic score described above occupies a central position. Besides social, biological, and game-like rule processes, it was primarily the technical functioning as well as the contents of media apparatuses that were used as ‹structure generators,› for example in Cage's «Imaginary Landscape No. 4,» in which the tuning and the volume of the twelve radios were adjusted according to a time schedule.

At the beginning of the 1950s, concretion of the works was still confined to professional musicians. During this period, John Cage, for instance, backed away from any interaction with listeners, because in his opinion, during the realization of open compositions only trained musicians could resist the temptation of sinking into musical cliches. Cage's objection to interacting with listeners illustrates a central problem: How can the competencies of music experts (composers, interpreters) be brought together with those of the listeners? How can the meaning of their

interaction be conveyed to listeners who are not musically trained in such a way that they act in a ‹musically meaningful› way?

The solution the experimentalists had for this was to expose the intermedial structure in their interaction: the use of technical or other generally familiar systems that could also be understood and operated by the musically untrained. With this approach, the audience can also take on the role of the interpreter. «Maxfeed» (1967) by Max Neuhaus resembles a transistor radio; however, it produces the screeching and hissing sounds itself. The audience consists of only one person, who determines the sound sequences using the dial settings he is already familiar with from his own radio.

As a structure generator, intermediality in the first place aids the composer in finding new structures. At the same time, intermediality is used as a point of contact for the recipient so that his interaction can follow a consistent line. The logical consequence of this development is the step from the concert performance to the installation situation, which the