At the March 2008 conference of the Association for Recorded Sound Collections held at Stanford University, audio historians played what they claim is the first recording of the human voice. It is a presumably female voice singing Au clair de la lune, though the distorted quality of the 10-second recording renders the words no more decipherable than the singer's gender to an untutored ear.1 The recording was made in Paris in April 1860 on a 'phonautograph' invented by Edouard-Leon Scott de Martinville (aka Leon Scott), nearly 20 years before Thomas Edison patented the phonograph in 1877. Sound waves captured by a horn attached to a diaphragm vibrated a stiff brush that inscribed the pattern of waves on blackened paper. Scott wanted to produce a visual inscription of human speech but had not yet conceptualised sound as something that could be audibly reproduced; that would be Edison's contribution when he replaced Scott's paper with a more pliable and durable substance: tin foil and later wax cylinders.2 The recent recovery of Scott's early inscription foregrounds the historicity of listening itself. As many scholars have pointed out, audition is organised differently by sound technology so that how we hear, not just what we hear, changes. Hearing becomes historical not just physiological; listening becomes technique. A new form of listening entails a new concept of sound itself. 'Phonautograph' means, literally, sound writing itself (which is the subtitle of Scott's 1878 book); thus the term ignores the very machine that is reproducing the voice. 'Phonautograph' suggests that the sound is literally there, textually inscribed on the blackened paper, and thus, technically, is not a re- production. Embedded in Scott's nomenclature is the germ of the debates that sound technology has aroused in the modernist era over the relative value of - and indeed, the very distinction between - original and copy, live and recorded, authentic and mechanically produced, sincerity and fakery, reproduction and representation. The confusion of those borderlines is graphically presented in the image of the dog with his ear to the horn of the gramophone listening to 'his master's voice' (a trademark first acquired by the London Gramophone Company in 1898 and used by Emile Berliner from 1900), as well as in anecdotes, cartoons, photographs and advertisements from the time in which people mistake the talking machine for a person talking, the mimetic representation for the 'real thing'. That slippage between the Uve and the recorded, the original and the copy, is precisely the achievement of sound technology; it is not a mistake but what makes it work. In that slippage lies the key to a new, modernist understanding not just of art in the age of mechanical reproduction, but of subjectivity itself. That kind of slippage is one that I have explored elsewhere in terms of 'passing'.3 Passing has conventionally been understood, especially in the United States, as a social practice whereby an individual assumes an identity that does not by rights belong to him or her.4 Most commonly, it refers to light-skinned African Americans living, or at least socialising, as white, which is how modernists would have understood the term. More contemporary usage expands the concept to include many different kinds of identifications across apparently distinct identity boundaries. The term is often deployed in a pejorative sense, as passing is likely to be associated with impersonation, appropriation or deception. Metaphorical uses of the term (for example, as in 'he's passing as a feminist') might seem to elide the particular historical conditions that motivated passing in its first cultural sense, such as laws against miscegenation, segregated public spaces and community-sanctioned violence. Even in its original historical meaning, however, passing was far more complicated than the notion of adopting a fraudulent identity would suggest. Passing was not just a response to rigidly imposed racial boundaries; it exposed those boundaries - social, legal, corporeal - as cultural, discursive and permeable. …