Alvin Lucier’s “I am Sitting in a Room” is a classic piece of feedback-based sound design. It consists of Lucier sitting in a room with 2 distant mics, 2 tape decks, and speakers. The recording begins with Lucier verbally describing the process of the piece, which is that he is recording his voice, and after recording, he will play that back through the speakers, and record that through the mics onto the 2nd tape deck. This continues for multiple generations. At first, you just hear reverberation of the rooms acoustics as he replays the tape into the room. Gradually, the resonant frequencies of the room (i.e. sinusoids whose wavelength divides the distance from speaker to mic) begin to stand out, and by the middle of the 2nd side of the lp the original recording is completely obscured.
Last month I wrote a max patch that implements a direct echo/reverb feedback loop to digitally simulate Lucier’s design, with a few extra features. There are several presets you can mess around with- the latter preset object implements a simulated acoustic reverb network from James Anderson Moorer’s 1978 paper ‘about this reverberation business’. Ive also included an example aiff file and its output after several passes through the loop.
NOTE OF CAUTION- if you start toying with the reverb network- the cascade output gain isnt normalized so the feedback tends to get out of control after a few iterations if you dont manually lower the gain so mind your ears.
