5! for Solo Percussion is the first of a series of computer assisted composition studies which use the perl scripting language as the main tool. 5! or 5 factorial means every possible combination of 5 things in this case that means 120 different permutations of 5 elements (percussion) – an interesting study for percussion using a sequence of patterns that are never repeated, there is a health dose of indeterminacy in parameters other than duration and note order allowed – a pretty tricky piece to play….
"5! for undefined percussion" duration ~14'
this piece is based on a sequence of 5 elements which are alternated in every possible way – how many different ways can 5 things be arranged? – 5×4x3×2x1=120
this is the also know as five factorial in mathematical notation 5! hence the title.
we have 5 drums called a b c d e
element 1 = [a a]
element 2 = [b]
element 3 = [c]
element 4 = [d]
element 5 = [e e]
so the initial set is
aa b c d ee
then the first permutation is
aa b c ee d
and so on through the 120 possible variations
these 120 variations are then mapped on to a repetitative rhythmic structure which comprises the variation followed by its retrograde.(there are also some complex “kinks” in this system – which dont need to be gone into here.)
this means the piece never repeats a pattern through out its duration -this makes it tough on the brain to play…
the piece comprises three sets of such permutations mapped on to three different rhythmic structures
A constant 16th notes
B more complex rhythmic structure
A’ simple rhythmic structure
the piece has no other structural markers, such as loud queit loud structures and so on – the perfomer may impose these structures on the piece them self
- my role as a composer in this piece is to present a set a of naked mathodical
variations and a basic rhythmic outline and leave the rest up to the performer. dynamic structure could be imposed on the piece variations in accents could be improvised or composed on top of the piece at the moment there are some articulations and attacks on the piece – perhaps these should be removed and left entirely up to the perfomer/arranger/co-composer even the instrumentation is left up to the performer – its just for 5 things these could be a set of tom toms, a bunch of scrap metal.. whatever!
it could even be multiple sets of 5 things which are alternated
section 1 – 5 tom toms
section 2 – 5 pieces of assorted scrap
section 3 – 5 pitches of a vibraphone
or the instruments could be alternated on a more free level – 12 bars of this set, 9 bars of that set, 15 bars of the next set and back to 12 bars of the first set… whatever… its completely up to the performer in this way the composition is a completly collaboative arrangement where the performer prepares a version and shares authorship of that version with the composer. The idea is to keep it as “free” as possible – that freedom also extends to the way it is copyrighted. It is released under a copyleft licence http://www.gnu.org/copyleft/
which means any derivative version may be made from the piece so long as this is also released under the same licence.
the code is viewable here:
https://code.goto10.org/svn/rob/the-five-compositions/5forpercussion/sgen.pl
and the pdf score is downloadable here:
https://code.goto10.org/svn/rob/the-five-compositions/5forpercussion/output/score.pdf
