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[Dear friends: This page was last updated in 2003. Please see
my current research
For the past several years the primary area of my computer music
research has been invesigation into methods of synthesizing dynamic
with the aid of computer technology. My work has examined stochastic
procedures, realtime control interfaces, and artificial life most
both investigated pre-existing computer music methods and software and
have designed and written my own. The four examples of my work shown
If you wish, you may download
a PDF document summarizing these projects by
I have also written short essays on the process of composition of
several of my pieces, including Gilgamesh
I have also completed research into the effects of user interface
design on computer music composition, and techniques for building
music performance instruments. Email me
for more information regarding this work.
Appliance: An Interactive Installation Performance
|Figure 1: Performance
the spring of 2000 violinist Maja Cerar, sculptor Thomas Charveriat,
and I embarked upon a collaborative
project entitled `Appliance,` which was an interactive performance
installation for violin, electroacoustic music, and mechanized
performance, the violinist wore a sensor glove to communicate with a
Max/MSP patch that controlled a delay line and playback of samples.
also operated a footswitch that controlled the activities of the
sculptures, which were connected into a network (Figure 1).
The sensor glove is worn on the violinist's right (bowing) hand (Figure
2). The glove is handmade from clingy lycra with open fingertips to
better bow control. Three force-sensing resistor (FSRs) are attached to
the index, third, and fifth fingers of the glove, and an accelerometer
(tracking X and Y velocities) is positioned on the back of the hand.
Wires from the glove's sensors and the accelerometer unite at a serial
which sends the data to a Pic Microcontroller residing in a small
switchbox. The chip translates data coming from the glove into MIDI
and sends this out to a MIDI interface and the central computer.
MIDI cable feeds into a Macintosh laptop running Max/MSP and a patch
built specifically for this piece (Figure 3.) The motions of each
mapped to control an individual aspect of performance: delays on/off,
samples on/off, and changing the currently active sample bank. The
data, originally intended to be used to control panning and amplitude,
was eventually ignored in performance. The delay time can range from
second to 5.0 seconds and is controllable from the computer, which is
operated by a second performer. The amount of delay feedback is also
at the computer. The samples are brief (0.25 to 3.0 seconds) and
contain a mixture of violin sounds and other percussive sounds.
In addition to the controller glove, a small microphone is mounted on
the violin and this signal is also fed into MSP. Using the Miller
fiddle~ object, we track note onsets, envelopes, and pitch. This data
is used to trigger samples when the sampling function is turned on
FSR.) We use the MSP groove~ object for sample playback, looping short
percussive samples to match violin notes' amplitude envelopes and
samples according to the estimation of the violin's current pitch.
The sensor glove
Each sculpture is composed of motorized elements mounted on a sheet of
metal and elegantly laid into a burnished aluminum suitcase. Most of
mechanisms of the sculptures create both motion and sound. Each
sculpture also contains at least one microcontroller chip, programmed
in BASIC to
define the behavior patterns of that sculpture. Because of limitations
of both the mechanics of the sculptures and the memory of the
each sculpture’s behavior is limited to being a set of loops
of rhythmic patterns.
Because the microcontrollers were not designed with musical
applications in mind, programming anything more complicated than a
quite time intensive. In order for the microcontroller to play a
rhythmic patter one must calculate the exact number of milliseconds
subsequent note onset in the patter, type in BASIC code using these
values for every note of the music, and then load this file into the
microcontroller. Obviously, this method of composing musical ideas is
quite non-intuitive and can be both frustrating and time-consuming, as
composer cannot hear what s/he has programmed until after the code has
been loaded into the microcontroller. To make the process easier, we
interfaces reminiscent of an analog sequencer in Max/MSP to program the
sculptures. These allow one to quickly compose rhythms with both
visual feedback. This intuitive interface makes it easy to set up
sophisticated polyrhythmic patterns, and then at the push of a button
BASIC code needed to program the microcontroller.
'Appliance' Max/MSP patch
The sculptures are connected
network to coordinate their activities. The violinist operates a MIDI
footswitch to cycle though a
pattern of behaviors of the sculptures. When activated, the mechanism
of a sculpture begin to move and make noise. Each sculpture is miked,
signal is mixed with the violin and the MSP output for amplification.
Each performance of the piece
highly improvisatory. The intention was to set up a system of
possibilities for the musician to explore-there is
notated score at all. We made two public performances of the piece, and
the second of these was recorded onto video (available upon request.)
placed more documentation on this project at the website
of sculptor Thomas Charveriat.
Other examples of my research include Juicer
a realtime DSP instrument; Ripples
a stochastic composition system; and Treembre
a SGI/Linux application. The Treembre, an attempt to hierarchically
organize elements of timbre and animate them in time.