Three radios are set up at the very beginning of the piece but playing only silence. Each is tuned to a different radio station. The radios are set up in a line with a space between them, with the viola player standing in the fourth position in the line.
The three radio stations correspond to the frequencies of three low-powered radio transmitters placed in the venue. Each is connected to a channel of the multi-channel playback device.
A microphone is unobtrusively placed in the space and begins recording when the viola player starts playing.
After a certain amount of time, the first radio starts playing back the recording.
After two more periods of time, the remaining radios also join in, so a canon accumulates.
So far, I've only performed this once and the performance officially "failed" - because I forgot to sit beside the microphone, meaning it only picked up a very, very quiet signal. Once I realised, I was forced to play very quietly to compete with it (which then made the later parts of the canon even more quiet), The YouTube clip here is from that performance - it was somehow a nice effect even though my idea didn't work at all
I think the piece has legs though!