The sound of this installation emanates from several sources: metal plates and instruments created by Paul Stapleton, suspended and equipped with a system of excitation that makes them appear to ‘play themselves’. It is thus produced by inducing the instruments to vibrate, rather than necessarily being transmitted from speakers. The frequencies which excite them are in part pre-determined, and in part based on real-time synthesis according to physical modelling. The musical work ‘performed’ is the Adagio of the ‘Dissonances’ quartet of Mozart; this version lasts approximately ten times as long as the original. Several performances, including recordings by the Quatuor Diotima for this project, were proportionally time-stretched so as to coincide temporally, and then stretched again or transposed without time correction. Frequency bands from these recordings were then chosen according to the resonant properties of each instrument in order to provoke spectrally augmented responses from them; thus the Adagio is performed by objects who render the materials according to their own specificity, in a metaphorical relationship to the addition of individual instrumental timbre to the notes of a score. The work was premiered at the centquatre in June 2010 (Festival Agora 2010; funding from SACEM; technical support: IRCAM and SARC).