English: 40 megaphones of different sizes and capacities are fixed to an aluminum grid made in the shape of a bell. All audio inputs are grouped together and connected to one single microphone. The microphone is hanging in the center of the bell just below the megaphones. Only a temporary de-energized system prevents the inevitable audio feedback. As soon as the visitors disturb the microphone from its suspended state, the audio system automatically starts up and the deafening roar of a 40-megaphone chorus of amplified feedback collapses on the bell-ringer.