lewis keller back to works
raining partials

Click here for a short video of the piece.

An installation created for SoundWalk2007. Raining Partials uses 6 homebrew drumming robots controlled by Max/MSP via an Arduino microcontroller. Each robot pounds out a steady rhythm and emits a sine tone from its internal speaker. The rhythms and sine tones correspond to the first 21 partials of the harmonic series and can be selected by the viewer via a small knob on each robot. The sine tone emited is a power of two (therefore an octave equivalent) of the rhythm being played. For example, if the robot is pounding out 1 beat every 2 seconds (i.e. at .5 hertz) its sine tone is tuned to 512 Hz (0.5Hz x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 = 512Hz), if it is pouning out 1 beat every 3 seconds (i.e. at .3333Hz) its sine tone is tuned to 341.33 Hz and so on. The difference between a pitched sound and a steady rhythm sound is only a function of our perception and Raining Partials allows the viewer to bridge this perceptual gap. A clicking rhythm is "sped up" to the point where we no longer perceive it as a click but instead perceive it as a steady tone. Raining Partials allows the viewer to explore the natural phenomenon of the harmonic series in a visceral way that equates the (slow) passage of time with the (fast) perception of a pitch. The robots also have a clumsy, handmade aesthetic which draws in the viewer highlighting the dichotomy of the high-tech computer control of scientifically observerd properties of sound with the low-tech and immediately graspable phenomenon of a steel can being struck while emiting a pure tone.