LUIGI MARINO

musician

Interaction 2 (2018)

For any source and 6-relation-interactive system


Interaction 2 is a work that uses the computer's analytical capabilities to surround the performer's gestures with an immersive synthetic landscape. This landscape requires no intervention other than the sounds produced by the performer for its whole development. These sounds are converted into a wide variety of data which are then recombined to generate all the aspects of the computer's response. The computer's output is entirely synthetic and there is no use of sampling or timeline sequencing.

The work is divided in two distinct sections. The first one is responsive to the sounds produced in that exact instant, but its response is generally tangential: the spectrum analyzed is spread over a larger timespan, and often the computer recombines data coming from sounds produced at different time. The second section uses all the data accumulated during the first section to generate an independent landscape with close formal ties to the sounds produced by the performer in the first section.

In this version I'm driving the system with a classic from the '70s, the crackle box. The crackle box is a circuit designed by Michel Waisvisz in 1974. The original circuit consists of an operational amplifier (LM709) whose connections are brought on the control surface, and left open. The user, touching them, closes the circuit using the body as conductor. The sounds produced are related to the resistance of the body, and the amount of pressure applied on the connectors. The classic crackle box used the integrated circuit LM709. Unfortunately the LM709 is not that easy to find, so instead I used the schematics of John Richards's bed of nails, which uses a far more common IC, the LM358. The op amp inside the LM356 is more stable and less prone to surprises, but in the bad of nails this is compensated using both the op amps on the IC, basically creating two crackle boxes feeding back into each other. On top of that there is a white noise generator made amplifying the background noise of a small 10 Ohm resistance connecting pin 2 and 3. The connection is done manually, pushing with the finger the resistor on the pad, so it's possible to control the white noise in a fairly performative way.