Hello World by Yunchul Kim.

From Interactive Architecture:

Hello world is an installation by Yunchul Kim that contains a codified audio signal that circulates in a closed (feedback) system, consisting of a computer, a speaker, 246 meters of copper tube and a microphone. By using the acoustic delay of the tube system, it is possible to store data. The longer the tube, the greater the time delay, which leads to greater memory capacity. In addition to this a screen shows a visual representation of the information traveling around the system. If a participant makes noises near the installation or hits the copper piping it interferes with the audio signal loop. For me what was most interesting was the play on standard architectural materials as a way of transmitting data and the way that anyone can experiment with creating interference within the system by simply making different noises.

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