Radio, arguably the most influential of the new media that were introduced in the early 20th century, has received surprisingly little theoretical attention. Whereas Film Theory is now fully institutionalized as an academic subject (which is taught at specialized programs and departments, and is discussed by members of professional oganizations in specialized journals), and we currently witness the emergence of a theoretical discourse on computer games, the theoretical literature on radio remains rather scant. The paper proposes the thesis that the lack of theorization of radio can be attributed to the fact that radio confronts us with the materiality of a disembodied human voice. The grain of the voice (i.e. its corporal materiality), as Roland Barthes has famously argued, is that which cannot be captured by semiotic or structuralist theories - the theories that have played a pivotal role in the institutional success of film theory.

The paper opens with a considerarion of the notion of the 'grain' of the voice, addressing both Barthes and Lacan, and then turns to the discussion of radio in Germany in the 1920's and 30's in essays by Brecht, Kracauer and Benjamin. These writings present us (on the one hand) with sophisticated theories on the political functions of radio, but they are (on the other hand) also marked by a confrontation with something that resists integration in the authors' theoretical musings, something over which their theories stumble. This stumbling is unwittingly highlighted in the Lehrstücke that Brecht developed for radio, Der Jasager and the Ozeanflug (both 1929/1930). It is exactly the failure of these radio-pieces - and Brecht's subsequent abandoning of his radio-project - that point to that which is specific to the medium of radio, and therefore opens the door to the development of a possible radio theory.

Yasco Horsman is lecturer in Literary Studies at the University of Leiden, The Netherlands. He is the author of Theaters of Justice: Judging, Staging, and Working Through in Arendt, Brecht, and Delbo, published with Stanford University press, and has researched and published on contemporary literary theory.