#acoustic composition

I recently completed (a first draft of) a solo percussion piece titled Peak for Judith Shatin's seminar class. The instrumentation of the piece is below:

The performance notes read:

This piece explores arm independence and the smooth transference of energy between multiple instruments within a gesture. Care should be taken to make these transfers as smooth and convincing as possible. More explicitly, the individual continuity of multiple simultaneous lines (played by the separate hands) is more important than absolute precision of the collective rhythm.

There should be a sense of energy continuing through each gesture, particularly within silences (i.e. each note should lead to the next). Likewise, the energy level of each section should feel relative to the sections preceding and proceeding it. Total running time ranges from 6 to 7 minutes, depending on chosen tempo and lengths of fermati.

This piece consists of 5 sections. First is the introduction, which establishes the conceptual gesture that gets used throughout the piece: a rhythm played on a single instrument that rises, peaks, and falls in volume and how it can relate to another similar "peak" on a different instrument. The glockenspiel is not used in the introduction.

Here is the piece's key:

And the "Introduction" of Peak

Next is a section with material that spawned from an earlier, simpler (and more linear) idea for the piece, "complexified" in this form through substitutions and rearrangement. The premise is the following: the "peak" gestures are played on the drums, dovetailed into one another, with a glockenspiel gesture punctuating the "top" of each "peak". In the first realization of this concept, each series of 6 peaks (grouped into 3 + 3) was rhythmically grounded in one subdivision of the tempo of the piece (quarter note, eighth note, etc.) and as this subdivision got smaller the number of notes in the glockenspiel gesture would contain more pitches (1 to 2 to 4, etc.). Further, these pitches were chords built on top of a simple descending line (C,B,Bb,Ab,G,Gb).

The section as it stands now varies the subdivision of each tempo and corresponding number of notes in the glockenspiel gesture with each "peak", increasing in intensity for the whole of the second section. The speed within each gesture also becomes more varied as the section progresses (starting with static quarter notes but progressing to gestures that start with half notes and speed to triplet eighths, for example).

Next is the meta "peak" and plateau of the piece, a section that explores playing the tambourine by shaking (along with the shaker) and also interjects a climactic gesture in the glockenspiel: an A5 (a pitch that does not show up in the previous section) that crescendos/speeds, then diminuendos/slows, representing a bleeding of the "peak" gesture concept into that instrument and clearly separating the piece into two halves.

The fourth section returns to the texture of the second section except that the melody is ascending and modified (F,G,A,Bb,C,D) and the subdivision generally gets larger as the section progresses. New subdivisions are explored (dotted eighth, for example) and the vocabulary for the relationship between consecutive "peak" gestures is expanded from the second section.

Finally, the piece ends with an "epilogue" that explores the delay between two "peak" gestures briefly, before ending monophonically in the muted snare and then the muted low tom.

"Epilogue" of Peak

Switching gears to an entirely acoustic piece, I recently finished composing a piece for solo flute titled State Change. The program notes read:

Many substances exist in different phases of matter or "states". When external energy is applied, solids becomes liquids become gases, and upon the cessation of that outside energy a gas becomes a liquid becomes a solid. Notably, during some state transitions properties of the substance change discontinuously, resulting in abrupt changes in the volume or mass of the substance.

This piece explores the sonic analogy of state changes, modifying the parameters of the sound of the flute to transition between different textures ("states").

My process for composing this piece was a new one for me. Taking inspiration from advice given to me by Tom Lopez (who mentioned that it was a compositional technique used by Morton Subotnick) I first created a "Parameter Map", which included parameters such as pitch, volume, and "airiness" mapped over time, with the time dimension striated into 24 discrete segments. The solid black areas correspond to the value over time of a parameter.

State Change Parameter Map

I then took the parameters at the start of each of the 24 segments and represented them as the first note in each of 24 measures in a score with corresponding pitch, note length, volume, etc. (e.g. D4, quarter note, mezzoforte). I call this document a "Notation Template".

State Change Notation Template

From here, my compositional goal was to "fill in" the measures, making sure that transitions between different parametric values (molto vibrato to no vibrato, for example) were smooth and interesting. This part of the process was the most intriguing to me. It gave me freedom to create interesting gestures while not having to worry about the overall trajectory: at all points of the process I knew the goal of the gestures I was creating and what trajectories spawned them. Put more colloquially, "where I was coming from and where I was going to" was known, because of the notation template and parameter map.

Ultimately, I ended up modifying some of the timings and parametric values, but the process helped me to create a piece and formal structure that I otherwise would not have created. My favorite moments in the piece are those that mirror the "abrupt changes in... volume or mass" alluded to in the program notes, times when the changing parameters interact momentarily to create a new texture for a moment before diverging.

State Change Final Score