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NOTE: This is an old project. Please see my main research page for more recent projects and software.
3. Treembre: A Hierarchical Approach to Sound Timbre Construction
The Treembre project is a realtime graphical interface for creating and
manipulating sound timbres. Working from the established premise that
complex sound can be dissected into a set of simultaneous dynamic sine
waves, Treembre gives a sound designer or composer the ability to
manipulate these simple waves within the paradigm of a hierarchical
tree structure (Figure 1.) Thus, while each component of the sound
individuality, these units may be grouped into larger entities. This
grouping allows one to create intelligent relations among the sound's
and manipulate these collections as single regions. The tree-like
interface allows the user to quickly and easily create these relations
accomplish complex sound processing tasks, listening to the evolution
of the sounds with every adjustment made.
Treembre interface (SGI 02)
Treembre was written in C for SGI Irix platform, using XWindows and
Motif interface tools. The program generates sound data based upon the
of tree nodes or "leaves" within a Cartesian plane in which frequency
rises from left to right and amplitude rises from bottom to top (Figure
node of the tree represents one sine wave component of the current
sound. Since complex sounds may be composed of thousands of such waves,
is to eventually allow the nodes to represent groups of sine wave
components. These groups could be specified by any desired criteria,
frequency bands, overtone series, amplitude ranges, and so on. Ideally,
the user would be able to "open" and "zoom in" to one set of these
a time, manipulate it, "zoom out", choose another, and so on. This
would combine the ease of the current interface with a more precise
control while avoiding the information overload that would result from
viewing all of the frequency components simultaneously.
Another goal is to eventually allow one to create and save multiple
configurations and then use realtime controls and/or algrorithmic
interpolate among these, creating highly organized and rich sound
structures. Given the ever-increasing speed of microprocessors, I
believe this is
a realistic plan.
In its present form, the Treembre application is able to continuously
play sound based upon the current configuration of its nodes and will
realtime as any node or group of nodes is moved on the screen. It
synthesizes the sound in a two-step process: First it traverses the
tree to gather
the current data for each node's frequency and amplitude. Then it sends
the sound data to RTcmix, the realtime sound synthesis and processing
environment created by Brad Garton and Dave Topper at Columbia
University. RTcmix captures the sound data and synthesizes the
composite texture using
simple additive synthesis of wavetable sine oscillators. Another simple
alteration would be to allow for substitution of any desired wavetable
during sound playback, to enrich the resulting timbre with added
partials; but this has not been explored yet.
Originally written on the SGI Irix platform, Treembre was ported to the Linux platform by Brad Garton in 1999.
For more information on Treembre, please email me at
Other examples of my research include Appliance, a system for interactive
performance with sculptures; Juicer, a realtime DSP instrument; and Ripples, a stochastic composition system.
A brief bio of Doug
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of Douglas Geers. © 1999 Douglas Geers.