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About the project

I'm a composer and lecturer at the University of Leeds, UK. As part of our undergraduate composition teaching we introduce various flexible generative techniques, and an expectation that students write a commentary that outlines their compositional process. To give the students another example of how this can be done, I've decided to compose a piece [jump to final piece] for the student new-music ensemble that explores several of these techniques; to augment existing examples, and give a more first-person account of using them. This blog follows my process as I compose using some techniques that I've taught often but wouldn't normally used myself: see here for examples of what I do usually.

[Impatient? go straight to the finished score, or watch the video]

Here's what I begin with:
the ensemble is unusual to say the least, but I like a challenge!3 fl, 2 cl,  sax, tpt, cornet, euphonium, perc, piano, guitar, celloRehearsals begin in February 2018 with performance in…
Recent posts

Opening Section + Magic Squares

This section has no solos, it's a simple contrast of two strata: (1) descending rapid scales, and (2) sustained chords swelling and receding. Listen to the opening page (score below) here:
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The pitches for both are derived from the magic square. The chords are most straightforward, they simply read the horizontals of the square as 6-note chords. The piece starts with the uppermost vertical (the main material + high G), and works its way down.


EG#DF#A#GBFAC#A#DG#CEC#FBD#GFAD#GBG#C

Sax & cymbals duet

The second section (bars 34–71 of the finished score v1) of the piece is an improvised duet for tenor saxophone and bowed cymbals. I've already referred to the ensemble part for this section, see here for an explanation of the system used to generate the asynchronous ensemble part from the magic square.

The duet uses exclusively multiphonics on both instruments. "Multiphonics" are not chords (collections of single notes played simultaneously on different vibrating objects), rather they are multiple-sounds, metastable vibrations where more than one pitch is vibrating simultaneously on thesame object sothey interfere with each other to form complex timbres of difference tones. Playing multiphonics requires practicing a specific skill to learning to balance the multiple-pitches. For saxophone, the tonal flexibility of the usual monophonic (single pitch) technique is sacrificed because the multiphonic will only stay balanced with a very specific mix of embouchure-position, b…

cello solo v2 - orchestration

Re-working the generated part: Before I get to orchestrating the cello solo, I decided I need to re-work the generated line. The previous line (ex.1 below) wasn't too practical, and didn't give the cellist enough leeway to work with the prepared-string to bring out the desired sounds: the whole point here is that the preparations allow for different harmonics and multiphonics to emerge, and that the tablature-style notation constrains the player's actions to limit what specific sounds emerge.

In the notation (as explained in earlier post) there's a 6-line stave to indicate not pitches but bow positions, between the preparation (bottom) and bridge (top); essentially sul-tasto to sul-pont. The part mostly only uses the right hand for playing, with the left hand occasionally used for timbre variation through interference (see b.143–145).

To generate the part, I allowed the isorhythm (ex.2) to run for nine iterations of the pitch line ('color' seems somewhat meani…

Finished Piece (v.1...)

The concert is on May 4th, so at some point I had to finalise the piece, though I could keep tinkering forever. Here's the full score as of 12/4/18, there will still be some minor changes I imagine; some things need tidying up, and at the moment it's missing performance instructions (most of which are in the score, but an instruction sheet will be added. Here's the structure of the piece:

bb.1–33 Opening Full ensemble contrasts material presented in two forms; static chords (reeds/brass/perc/cello), and falling “scales” (flutes/pno/gtr). technique: Magic square, randomness. 34–71 Saxophone & Percussion duet Improvised duet of sax multiphonics and bowed-cymbal harmonics. Ensemble plays Feldman-like gentle background of overlapping melodies and soft noise. technique: Magic square. Links: generating ensemble part. 72–115 Guitar & Piano duet Guitar and piano play almost together, pushing/pulling each other, the ensemble play sparse additions to support or undermin…

piano & guitar 3 - orchestration

[general apologies for the images in this post, which don't always link easily to the text. My parameter names kept changing over the few days spent composing this, which looks confusing now because the parameter names (descriptors) aren't always the same.]
Having generated the phrases for the guitar and piano, I need to decide how this 5-mins of duet will relate to the rest of the ensemble. I decided to use the Xenakis rotating-cubes technique to generate a phrase-by phrase orchestration behaviour. Crucially, this only defines the type and size of orchestration, not the specifics: I could have generated very specific limitations on instruments etc but wanted to keep this free to save time really, and allow a more intuitive shaping of that aspect. I also wanted to avoid this being too 'blocky' and only mirroring the phrasing of the duet, so I allowed for some orchestrations to reach forward or backwards into neighbouring phrases. My first thoughts on this is that I ne…

Piano and Guitar duet v.2 - realisation

It's been two months between deciding the system I'd use for this duet, and actually implementing it. Inevitably a few things have shifted, but it's essentially the same as described in the first post here.

Part of the delay was laziness about transferring the stream of numbers into notes on Sibelius, which it turns out was solved easily by using the 'seq' object in Max to turn the stream of numbers into a midi file, which could then be opened in Sibelius. Easy!

The other delay was in trying to work out how the notation would work to (a) allow the guitar and piano to be together but drift apart at times, and (b) still allow the ensemble to play over the duet without requiring the players follow the conductor too strictly. The delay was one of those situations where I decided to just let me brain work on it without me (mulling it over sometimes without actually thinking about it too hard), and then some helpful chats with other composers made it fall into place.

I …

Magic Squares

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I took my original 5-note sequence (E, G#, D, F#, A#) and extended it into a 6x6 magic square following Maxwell Davies' approach of (a) ensuring the sequence goes out of phase from line to line (because sequence of 5 pitches along lines 6 units long), and (b) transposing each subsequent sequence. The transpositions aren't always the same, because I was getting repetitions; because going up in minor-3rds ends up in the same place after four cycles (12 chromatics divided by 3 semitones = 4), so after the 4th cycle (when it should return to E) I transposed up a further semitone to push the whole cycle of four sequences a semitone higher than the first four. The square is (mostly) transposed by minor 3rds because the original 5-note sequence is whole-tone (the two possible whole-tone sets are six notes each), so minor 3rds give pitches not in the original whole-tone set. [commentary point] This solves the whole-tone problem of only having six notes to work with (or t…