![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1BD_aqH8Su5Q48ZSVCW4jsy3JFrfDKhQcjb7sOOnAHgMsVJSVP0qArxt0XMoy_jWEoo51aMZ1Q_bmq-94Piw7xhDWNsT2gBqPXr7T8rzhZ9RB5GVHjB3a2En5U-U_O8odJBoTpliduCls/s320/Feedback+Piano+1.jpg)
The instrument in this video was built by a Ph.D. student (Alloy Electric) in computer music at UCSD who builds real and imaginary instruments and programs audio effects.
"This is an instrument I originally built to make the sound design for Rosencrantz and Guildenstern Are Dead. It is a computer-controlled feedback loop which engages the strings as a sort of resonant memory. Any sound made in its vicinity will hang sustained in the air as it is slowly transformed. Its sound is at once familiar and alien, a fitting backdrop for the surreal world inhabited by these characters."
You can hear more of this stringed instrument among others on the album Diverse Recourse by Joe Beats.