Seth Kim-Cohen claims that discourses in sound art are typically concerned with audio phenomena to the exclusion of textual and institutional concerns. That is, we think more about the sounds themselves than the way that sound exists in relation to a broader discussion of the history and boundaries of cultural activity. Cohen critiques common conceptions of sound art through a boilerplate postmodernist lens setting his sights on Pierre Schaeffer's conception of the sound object, McLuhan's "essentialist primitivism," self-referential readings of Cage, conceptions of authenticity and the blues, and approaches advocating the primacy of audio perception. For Cohen, sound art ought to take a Duchampian turn, paying greater attention to the way that art "questions its own ontological and epistemological conditions."
In the Blink of an Ear is particularly useful for visual artists who will feel at home with the discussions on Greenberg, Krauss and Duchamp. But the polemical tone prevents Cohen from undertaking a more multifacted study of the approaches he critiques. Viewing authenticity only as a reference to an original, for example, Cohen neglects to consider authenticity as the ability to negotiate a discursive activity or as a kind of embodied understanding. For all this, Cohen ends up advocating something similar to the conceptualism of the seventies: a sonic expansion but theoretical reduction.
For a different take on sound art, consider Salome Voegelin's Listening to Noise and Silence: Towards a Philosophy of Sound Art. Voegelin's thoughtful, phenomenological work does what Cohen's does not: illuminates a rich set of sonic possibilities for the future of the genre.