The "modern" grand piano, perfected in the nineteenth century, consists of a keyboard, a set of metal strings and an ingenious mechanism of hammers and dampers, which serves as the transmission between the pianist's muscles and the strings. The wooden body of the piano amplifies the vibrations of the strings when they're hit by a hammer. In Piano Hero this configuration is "updated" and placed in today's context, using some of the typical artefacts of the 21st century: the keyboard now is an electronic one, the computer serves as the transmission and the strings are played by a virtual pianist -the avatar of the pianist of flesh and blood sitting on stage- while the wooden resonating body is substituted by a set of electro-mechanical speakers. But not only the "piano" is recontextualized. The mechanisms of "observing", as done by the audience, is also taken into the equation. The act of "observing" underwent a radical change of meaning in a society which is ever