Dan St. Clair : Sound Art, Sound Installation, and Birds
For an Intersection
(2010) sound installationFor an Intersection from Daniel St. Clair on Vimeo.
Russell House, Wesleyan University, Middletown, CT: May 2010. A line of 16 speakers hangs at one end from the interior stairwell of the house, and at the other end from an outdoor tree, passing through a open window. The speakers play a variety of synthesized sounds all originating from a single cricket chirp. The rhythms of the piece are organized using the Inhibitory Response Mechanism algorithm, an algorithm shown by Brush and Narins to reasonably approximate the chorus dynamics of the Puerto Rican "Co-qui" frog.
The IRM Algorithm
The timing of individual sounds is organized by the IRM algorithm. Originally developed for network data transmission in the 1970s, the IRM was adopted by Brush and Narins in 1989 (see citation below) in simulations of the chorus dynamics of the "Co-qui" frog in Puerto Rico. The algorithm has four possible states:
1 - preparing
2 - calling
3 - inhibited
4 - paused
Frogs "listen" to the calls around them during state 1 and at the end of state 2. If the frog senses that another frog is caling during those times, it advances to state 3, which delays the frog's next call for a bounded random length of time. Otherwise, the frog moves through states 1, 2, and 4 in succession. The effect is that the phase relations of a chorus are adjusted for minimal overlap of the calling period.
The following images display some of the results of the algorithm. The calling periods are filled-in black rectangles, and one individual occupies a single horizontal line.
Exhibited :
Russell House, Wesleyan University
Middletown, CT. May 2010 .