Thursday, February 14, 2013

Introductions, part 1

Well, there's just one introduction. It's the most unified section of the piece. It will actually have a standard score with a time signature, bar lines, and synchronized parts. I knew the kind of texture I wanted; it came out of an improvisation with Impulse back before the holidays. The primary gesture is based on the physicality of playing the piano in the low register, thumbs together, alternating hands playing "random" notes within a generally fixed range in a fast, regular pattern. The pitches aren't important except in that they should not overly emphasize any particular pitch. Of course, as we know from the history of serial music, it requires some kind of non-intuitive system to make an even distribution of pitches sound just right. In my improvisation a couple months ago I felt like I was getting the right texture intuitively, but when it comes to making decisions about pitches to go down on paper I felt I needed to go to the computer to generate a texture closer to my improvisation. Besides, while my improvisation felt right, without a recording I can't be objective enough about it (not to mention I can't transcribe what I played). Intuition is a dangerous place to spend too much time :)

I went to Max because it's very flexible. I built a very rudimentary patch that outputs MIDI information directly to Sibelius. Here's a picture:


The toggle in the upper left turns on the patch. The metro object bangs the toggle below resulting in alternating 0s and 1s. The 0s go to the "left hand" side of the patch, which generates the left hand notes, and the 1s go to the "right hand" side. Both sides are essentially parallel, generating numbers between 48 (the MIDI number for C3) and 48+6 (or 54, F-sharp3). The left hand side is then lowered 7 semitones, producing the range of F2 to B2. The result is alternating left hand and right hand notes, each hand covering the range of a tritone, which fits very comfortably under the hand.

Once I decided the length of the gestures, I added the objects on the right side of the patch to add a curve to the gesture (more on the length of the gestures below). The center pitch above is MIDI note 48 (C3), or 21 semitones above E-flat1, a tritone above the lowest note on the keyboard (i.e. as low as possible without the left hand running off the keyboard). During my original improvisation I moved gradually to the bottom of the keyboard, and I wanted to recreate that gesture here. I tried to descend by semitone every measure for 21 measures, but found the descent was too regular for my liking. By connecting the itable object to the transposition factor (see figure above), I could control the rate of descent. I simply drew the curve that I wanted with my mouse (of course, I had to set the parameter of the itable first--in the example above I knew I needed 377 notes, so the x-axis was set to 377). The transposition factor adjusts the center pitch, which is 48 by default, thereby lowering all the pitches proportionally. When the curve reaches the bottom of the itable, the transposition is 21 semitones down, for the bottom of the keyboard.

The form of the introduction

The introduction is around 2:20 in length, but it gradually dissipates into the main body of the piece making the ending of this section ambiguous. It represents no more than 10% of the entire work, and probably a little less. I first thought of it as a stand-alone, unrelated section, but now I think of it as crucial to the development of the three component pieces: In the beginning the three are integrated into one gesture, but during the course of this introduction, they begin to foreshadow their distinctive behaviors and come apart from one another. If the idea for the entire work is three separate pieces, the introduction tells the story of how they became separate.

The first 30 seconds or so is an extended reproduction of the improvisatory piano gesture I described above. Percussion and the electric guitar join in unison or octaves, dynamically coloring the piano's timbre. This is notated by 377 sixteenth notes. After one sixteenth rest, the same gesture is played again, but shorter this time--233 sixteenth notes. Then another sixteenth rest precedes a third gesture taking 144 sixteenth notes. There are twelve gestures like this, each getting shorter according to the Fibonacci series down to a one-sixteenth-note gesture. The rests between each gesture (#thevoid) get progressive longer according to the same series.

These rests between each piano/percussion/guitar gesture are filled in by harmonic series chords in the winds, strings, and sopranos. Conceptually, I just wanted static surface texture to contrast with the active sixteenth-note surface. However, as the piano's active texture is colored by the percussion and electric guitar, the static-texture interruption is also elaborated somewhat. The primary static material is found initially in the bassoon and clarinet (though these may change later in the introduction--it's not finished yet). The first static gesture is only one sixteenth note, so in order to avoid it blending too much into the piano/percussion/guitar texture, I orchestrated the event with some higher-frequency resonance. This resonance is found in the flute and string harmonics, and it is sustained somewhat longer than the single sixteenth note played by the bassoon and clarinet. The singers, too, project this idea of resonance with even longer (approximately two measures) passages of unisons and close-voiced harmonies that slowly change.

As the static gestures get longer they come to dominate the surface of the music. From a position of practicality the resonances must either get shorter (because the time between gestures is getting shorter) or begin to wash over the beginning of the next gesture. I will play with this, probably alternating between abrupt changes with no resonance and resonances that become asynchronous with the static event rhythm (think of waves crashing irregularly on a beach). The nature of the soprano parts as harmonically dynamic resonances will begin to change to more static material that will eventually lose prominence to the strings and winds, which will gradually become more active. The sopranos' movement toward stasis will foreshadow the beginning of sopranos' large-scale gesture, which begins quite statically. The winds/strings' growing prominence will signal, by the end of the introduction, the beginning of isorhythmic texture that will dominate those instruments' large-scale gesture. The piano/percussion/guitar part, with its curves in pitch space, foreshadows the tempo curves that will dominate the behavior of those instruments later.

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