"Catch 22 goes underground" was done in collaboration with composer Nicolas Varchausky and visual artist Daniel Trama. The piece was created applying the concepts of feedback and recursion to a specific site to transform its acoustics. The selected site was a 50-meter long underpass in Buenos Aires, which runs under a 6-way avenue and connects the Zoo with a large urban park in a nodal traffic point of the city. Eight speakers and microphones were deployed along the tunnel, facing each other to generate feedback. Each speaker-microphone pair was set at the height of a human head or torso, making it possible for people to interfere the feedback loop with their body. Visitors to the installation -or the unaware passer-by- could experience how their presence in the tunnel alter the system and, by doing so, the acoustics of the site.
Feedback loops were controlled individually with a computer to avoid infinite loudness growth, and to transform their sound, creating some sort of electronic feedback choir in perpetual state of instability. Movement sensors set at each end of the tunnel triggered changes in the system as people entered the installation; changes were set to gradually propagate from the opposite end of the tunnel towards the visitor's location. Right in the middle of the tunnel, two surveillance cameras and monitors connected in a loop built a visual analogy to the sonic experience. This absurd surveillance system constantly displayed the back of people facing it, making it impossible for visitors to see their faces on the monitors.
Finally, "Catch 22 goes underground" could be interpreted as a complex musical instrument or soundscape. The characteristics of the site -having both ends open to outdoor urban spaces- made it possible for the system to react to ambient sound in an organic way, incorporating the sound of wind, voices, traffic, planes, birds, etc. to the sonic environment of the tunnel. We took advantage of this "performable" aspect of the system during the opening night of the installation "playing" an improvised set from the control booth using two networked laptops. During the performance, two members of the team sensed the sound pressure level at each end of the tunnel writing decibel values down with chalk on the back of the entrance walls.