Refractions (Armstrong, Peter McKenzie)




MP3 file (audio)
Peter M. Armstr... (Unknown)

MP3 file (audio)
Peter M. Armstr... (Unknown)

Performer Pages Peter McKenzie Armstrong (Rosegarden & Pianoteq)
Publisher Info. Edition Ottaviano Petrucci
Javascript is required for this feature.


MID file (audio/video)
Peter M. Armstr... (Unknown)

MID file (audio/video)
Peter M. Armstr... (Unknown)

Performers MIDI
Publisher Info. Edition Ottaviano Petrucci
Javascript is required for this feature.

Sheet Music


PDF typeset by composer
Peter M. Armstr... (2012/6/19)

Publisher. Info. Edition Ottaviano Petrucci
Misc. Notes Engraved with LilyPond 2.13.32
Javascript is required for this feature.

Javascript is required to submit files.

General Information

Work Title Refractions
Alternative. Title 12-Tone Chords on an All-Interval Row
Composer Armstrong, Peter McKenzie
I-Catalogue NumberI-Cat. No. IPA 23
Movements/SectionsMov'ts/Sec's 2
Year/Date of CompositionY/D of Comp. 2012
Dedication in memoriam Phil Winsor
Average DurationAvg. Duration 90 seconds
Composer Time PeriodComp. Period Modern
Piece Style Modern
Instrumentation Auto-sequencer

Navigation etc.

Composition Notes

In the mid 80s I wrote the first of several algorithms collectively named "IntLens", which, given any
pitch class series (probably a 12-tone row), complemented &/or compounded its intervals in all
combinations of selection by class, outputting each result as a chord graph with associated
statistical goodies.

Now for a sounding realization of that idea, I have chosen input series 0 1 4 2 9 5 11 3 8 10 7 6,
Mallalieu's all-interval row (the most perfectly self-similar, with second half retro-inverting the first),
to ensure that chord-to-chord contrast will stem maximally from registral differences and minimally
from source-specific quirks.

Viewing the total process as one of expansion, I have assigned importance to the relative pitch
density at a chord's extremities (top/bottom), and made such densities determine for each chord
both duration (via tempo settings) and volume level.

To avoid notehead collision in the tighter-registered chords, each chord is scored in two columns:
one for black keys, with a collective sharp sign; and a second for whites, with a collective natural
sign.  The column pair is to be read as sounding at once.

There are two movements, applying alternate ordering criteria.  The first sequences chords outerly
by range, innerly by density; the second reverses this sort priority.

Not explicit in the score (though implemented in the audio files) is consistent chord arpeggiation.
This is applied: in Movement I as "rolls" in row-sequence order (rather than up or down), and in
Movement II as "unrolls" -- correspondingly ragged endings following block-chord attacks.

Refractions is dedicated in memory of Phil Winsor, who mentored the IntLens project during my
season at UNT and once corralled me as keyboardist in an exhilarating chordal adventure of his
own.   He dared anything graced with discipline.