My primary research interests involve the perception, modeling and compositional applications of timbre. In my works, timbre acts as a catalyst for exploring new soundscapes, time, space, perception, and color. My portfolio illustrates a trajectory through which composing with timbre yielded new creative insights and compositional techniques.
Compositional Timbre Model
My primary objective as a composer is to write beautiful and stimulating music. For me, “beauty” is embodied by temporal, and in particular, timbral attributes. Over the past seven years I have developed my own compositional model in which the “color” and “texture” of available sounds are derived from multidimensional models of timbre spaces.
The problem with timbre is that it is ill-defined. Unlike pitch and loudness, there is no simple, objective, or single dimensional scale that describes this phenomenon. Timbre can however be described as a multidimensional attribute of sound and “continuous perceptual dimensions correlate with acoustic parameters corresponding to spectral, temporal, and spectrotemporal properties of sound events.” As timbre became increasingly central in my composition, I adopted a hybrid model that integrates both the “color” and “texture” of sound, and incorporates both static and dynamic attributes of timbre. The “color” of sound is described in terms of an “instantaneous snapshot of the spectral envelope,” while the “texture” of a sound describes the “the sequential changes in color with an arbitrary time scale.” This view of timbre has been developed at CCRMA by Hiroko Terasawa and Professor Jonathan Berger, and hints at two important compositional elements in a piece: 1) static, vertical pitch and chordal structures, and 2) dynamic, horizontal temporal processes. While these elements are important, this definition is still rather vague as to the descriptive factors of timbre.
While I have been attracted to other composers’ and researchers’ timbre models (including models by Pollard & Janson, Grey, McAdams et al., Wessel, Penderecki, Spahlinger, Saariaho, Grisey, Slawson, Lerdahl, Cogan and Erickson to name a few), I have sought a model for my own purposes that is less limited and open to deeper dimensionality. The goal for creating my own compositional timbre model was to find a way to allow the perceptual properties of timbre to address and control any aspect of a composition across multiple dimensions.
For my works I propose a set of two interlocking spaces or “cubes” as I like to visualize them. The first cube essentially controls the frequency components of the sound. This compositional timbre space has the following three dimensions: spectral flux, spectral centroid, and noise-to-pitch ratio. The first dimension, spectral flux, measures the Euclidean distance between two spectra, or rather, the change of spectral energy over time. By extension, this dimension can be used to control rhythms or the frequency of pitch changes. This analogy provides a measure of density in time analogous to spectral flux at the intra-event level. For example, in my model, a sound with high flux means that there is a high rhythmic activity, or that pitches are changing quickly, while a sound with low flux would be one in which there is either a low rhythmic activity, or the pitches are stagnant.
"Virtually any aspect of a composition can be viewed and decisions can be made based on these two combined spaces."
The second dimension controls the noise-to-pitch ratio and is similar to Saariaho’s “timbral axis.” On one end of the axis there are sounds that are mostly “pure” pitch—that is, sounds that are close to sine waves. By contrast, the other end of the axis is “mostly noise.” 
The third dimension controls the spectral centroid, or rather, the average centroid over time, and controls the brightness and darkness of the sound. For example, if the space was evaluating the spectral centroid for a violin sound, this axis would have four reference points--con sordino, sul tasto, normale, and sul ponticello—plus every shifting possibility in between.
Cube I is however, missing key information, namely: the quality of the attack, the dynamic level, and the length of the event entering into the space. To solve this dilemma I use a secondary cube to inform these decisions. This second cube works in conjunction with cube I. The first dimension—attack—controls how the sound or gesture’s articulations are treated, ranging from no attack (or a smooth onset) to a sharp attack (sharp onset); the second dimension controls the length of the event, sound, or gesture that enters into the timbre cube; and the third dimension controls the dynamics. Virtually any aspect of a composition can be viewed and decisions can be made based on these two combined cubes.
What is interesting about this model is that the function of each dimension changes depending on the source material inserted into it, and the function of the desired result. For example, I could either place a sound into the space to learn more about it’s timbral characteristics, or I could map the instrumentation/every sound I wish to use in the piece onto the space’s dimensions and ‘see’ the possible coordinates. Using this model, timbre itself controls and informs the composition. It can be used to derive rhythms, generate a form, harmony, rate of material, or simply inform the orchestration of the piece. With this model, one can work with any sound, or instrumentation. While this is process is more intuitive than scientific, it abstracts the original sound and allows one to base a piece’s timbral decisions after an already existing acoustic model.
In my most recent works I have used nature sounds as stimuli and “everyday” sounds as material for my pieces. I am fascinated by the “color” of sounds and timing of events that surround us in our everyday lives. They are filled with rich material and offer incredible musical possibilities. With my model one can insert material into the space and zoom in and out of it as one desires. Similar to painting, with this model the composer not only gets to choose the “landscape,” the composer can also control the perception and magnification of the material. The dimensions change slightly depending on what one chooses to highlight. Similar to visual art, the resulting piece would not be a copy of the source, but rather a representation of it.
With each piece I compose I understand more, not only about timbre and the different ways to approach my compositional model, but also about time and space. With this model each composition serves as a piece of a puzzle whose image reveals a more clear and complete understanding of timbre.
 McAdams, S., Giordano, B., Susini, P., Peeters, G., & Rioux, V. (2006). A meta-analysis of acoustic correlates of timbre dimensions [Lecture slides]. Retrieved from McGill University: http://www.dafx.ca/slides/keynote3.pdf
 Rossing, T.D. (2012). Pitch and Timbre. Lecture conducted from Stanford University, CA.
 Saariaho, K. (1987). Timbre and harmony: Interpolations of timbral structures. Contemporary Music Review, 2(1), 93–133.
Reid's DMA Final Project: Composing Timbre Spaces, Composing Timbre in Space: An Exploration of the Possibilities of Multidimensional Timbre Representations and their Compositional Applications
This final project is comprised of three works completed over the past two years, and an introductory paper that briefly outlines the approaches to timbre taken in each piece. All three of the compositions approach timbre from a different perspective and explore the possibilities and compositional applications of multidimensional timbre representations. The final project does not present a comprehensive history of timbre, all the research that has been undertaken on the topic, or a complete account of the composers who have used timbre models. Rather, the models and compositions presented here are meant to provide insight into my own compositional thought process. The three original pieces illustrate a trajectory through which composing with timbre yielded new creative insights and compositional techniques. Emergent in these works is a common theme and exploration of: “timbre space” and “timbre in space.”
The first piece presented in this portfolio is Ostiatim, for string quartet. It explores timbre space as a morphing device for sculpting material. Ostiatim was premiered by the Jack Quartet.
The second piece, Clocca, for chamber ensemble, examines timbre space as a structuring device. Clocca was premiered by the Talea Ensemble.
Finally, the third piece in the collection, Occupied Spaces, for two piano and percussion, explores a series of timbral spaces, presented as “rooms,” which grow, shrink, and continuously shift in shape. Unlike Ostiatim and Clocca, this final piece explores timbre in space. Occupied Spaces was premiered by the ensemble Yarn/Wire.
Reid's Timbre Space
Part I (called Cube I) of Reid's 2-part interlocking compositional timbre space is depicted above. The first cube controls: the spectral flux, the spectral centroid and the noise-to-pitch ratio.
Part II (called Cube II) of Reid's 2-part interlocking compositional timbre space is depicted above. The second cube controls the quality of the attack, the dynamic level, and the length of the event entering into the space.
Reid's Timbre Space as it Relates to Ostiatim
In Ostiatim the spectral flux dimension controls the frequency and rhythm of pitch changes, the spectral centroid controls bow placement and mute usage, and the noise-to-pitch ratio controls bow and finger pressure.
Examples of Trajectories from Reid's String Quartet Ostiatim
Example 1. Ostiatim’s Fragment 1 - points in space for cubes 1 and 2
Fragment 1 (doorbell chimes) is an example of the exploration of a single point in space. The fragment is comprised of small bursts of material with sharp onsets. This point can be described as having a mid-spectral centroid, a mid-high noise-to-pitch ratio, and a mid-high spectral flux.
Example 2. Ostiatim’s Fragment 2 - points in space for cubes 1 and 2
Fragment 2 (door banging) exemplifies some of the possible trajectories that can be created in the space. The fragment has two parts: measures 8-14 and measures 15-17. In terms of articulations, the first part juxtaposes aggressive pizzicati with arco sounds, and the second part features delicate pizzicati and soft mid-noisy tremolos. Each part has differing spectral flux coordinates. The first part of the fragment has a high spectral flux while the second part has a mid-low flux. The spectral centroid has multiple trajectories. One can observe the movement in the second violin and the violoncello. For example, in measure 8 they move from sul ponticello to ordinario which can be viewed as a movement from a high to a mid spectral centroid. Another example can be seen in measure 12 with a movement back to sul ponticello. Here, the spectral centroid shifts back to high. In measure 13 they shift to sul tasto which can be viewed as a movement to a low spectral centroid. The violoncello then does one more movement to sul ponticello, and then back to ordinario in measures 13-15 which can be viewed as the trajectory of a high to low spectral centroid.
In terms of the noise-to-pitch axis, in measure 8 both the second violin and the violoncello move from over-pressured bowing to normale bowing. This can be viewed on the timbre cube as a movement from a high noise-to-pitch ratio to a mid-low one. The opposite motion can be seen again in measures 11-12 and 13-14. Furthermore, in the second part of this fragment (measures 15-17) the second violin and viola explore a mid-high noise-to-pitch ratio while the first violin (mm.15-17) and the second violin (mm.17) explore a mid-noise coordinate.