The first 2'10" of the recording are the section I refer to as the "incipit" of the piece. Although it may sound like some electronic effects are happening, this incipit is entirely unaccompanied. Those amazing sounds are all courtesy of the incredible Jen Baker, who can play what are called multiphonics on the trombone by singing at the same time as she is playing. If you're guessing that this is hard, you are partly correct; if you're guessing that this is very, very hard, then you've hit the nail on the head.

The incipit is a microcosm of the rest of the piece, a compressed rendition of what is to come in the piece proper. First (1), we hear soft pedal tones and Jen uses a special mute (a "harmon" mute) to gradually open up the harmonic spectrum. This work explores some basic ideas of the relatively new classical genre known as spectralism, a genre wherein the actual spectrum of a given note and timbre is explored compositionally. This isn't the place to explain the whole world of this, but the Wikipedia page on the topic seems to be fairly informative. At any rate, this is one of the primary aspects of the musical "zooming-in" that defines a ΘΣ piece.

After these initial notes the trombonist explores different versions of the same note (2) before returning to the spectral harmon mute idea, this time closing off the higher overtones (3). The next section is the multiphonic melody referred to above (4). Jen holds a single note on the trombone while singing a melody above it, thus creating the fantastic sounds you are hearing. The incipit concludes (5) with an insanely difficult glissando, where Jen has to sing starting on the same note but moving in the opposite direction. She finally lands on a pedal note, much like the beginning but a half-step lower (A instead of B♭). This is both the end of the "incipit" and the beginning of the main piece.

(1) The electronics enter and take over the pitch from the trombone. The spectral exploration provided by the harmon mute before is now entirely electronic (giving her a much-needed break). Listen very carefully to this section, and you should hear what initially sounds like a single low-note slowly "bloom" into a thick and dense chord. This happens because I take every individual overtone of the sound and gradually "tune" (or, in a way, "detune") them into equal temperament. If this doesn't mean anything to you, don't worry about it, just listen for the effect of these sonic components which subtly emerge and become pitches in their own right.

(2) The trombone reenters only to have it's note again grabbed by the electronics and subsequently ripped apart between the two speakers (this part sounds particularly cool with headphones). While the electronics go into an epileptic freakout in the background, the trombone plays a gently melody, but keeps getting sucked into the general tone of the accompaniment. The section builds to a powerful climax, but it is suddenly cut off before achieving its goal. The next section is a strange sort of death march, with the trombone soloist joined by an army of detuned MIDI trombones. Huge chromatic clusters result, but the note A is consistently avoided.

(3) Eventually the trombone tires of the march, and starts adamantly insisting on the missing A. At the same time, an A emerges out of the æther in the electronic accompaniment. It seems to be fading away into obscurity, but is suddenly brought back with...

(4) the section I call the "AM Cathedral". This section is analogous to the multiphonic melody from the incipit, but instead of having the trombone make the strange sounds, the electronics do, using Amplitude Modulation (AM) which is essentially the same thing as "ring modulation." Ominous cracks and rumbles reverberate while a barely audible trombone plays a quiet melody. When this is over, the trombone plays a mordant tune over an initially hesistant techno beat. This quickly degenerates into ever-wilder variations, building into...

(5) the return of the dual glisses, now with a massive, detuned electronic trombone choir for accompaniment. This builds to the same climactic passage as before, but this time it finally achieves it's goal (back to the main tone of the incipit, B♭), just before suddenly deflating. The trombonist makes various quiet sounds, trying impotently to keep the piece going, while a low B♭ in the electronics gradually loses its identity and floats away. Listen very carefully to this final note, and try to hold onto the pitch in your mind. At some point, it becomes impossible to hear it, as it just slips away like a wisp of smoke.