ACOF 2003 Participant - Alicia Grant

Alicia Grant

Alicia Grant's Centrifugue, was a composition written for ACOF 2003.

 

 

...There exist specific gestures within the melodic idea that plead for characterisation....

Program Notes - Centrifugue

centrifugal
moving or tending to move away from the centre.

centrifugal force
the tendency of a rotating body to move away from its circular path at a tangent. For example, a rider standing on a carousel feels himself 'pulled' outward as the carousel spins around. Centrifugal force is a fictitious force because it is a by-product of measuring coordinates with respect to a rotating coordinate system as opposed to an actual 'push or pull'.

centrifuge
any machine with a compartment which spins around a central axis, used to separate substances of different densities, etc.

centrifugue
a polyphonic composition where the main theme rotates away from its pitch centre (E) by progressive transposition up a tone. This motion continues until the theme finds itself back on its pitch centre, where it ends.

Composition Diary - April 2003

Recently I have become interested in the way that musical material can be structured to give the illusion of circular motion. I have composed a melody that repeats every eighteen bars where, at the end of each repetition, the melody is seen to have transposed itself up a tone. Defining the tonal centre for this melody as E, the theme is seen to rotate away from this centre until it finds itself returning to it, several repetitions later, an octave above.

The initial inspiration for this idea has come from contemplating the nature of centrifugal force. It is the tendency of a rotating body to move away from its circular path at a tangent. The typical example to illustrate this is when one rides a carousel and feels the pull outward as the carousel spins. Similarly, whilst my musical material is following a circular path it is constantly 'pulled outward' by transposition.

I have composed a small ensemble piece for eight players to experiment with this idea. I have set up pairs within the ensemble who play the circular melody in close canon (set a quaver beat apart) and then layered these pairs at different points to build a larger polyphonic texture. My intention now is to expand this texture even further in an orchestral context.

Returning to my analogy, I am now considering the function of a centrifuge. This is a machine with a compartment that spins around a central axis to separate substances of different density. What are the formal implications if I imagine the different timbres possible within an orchestra act similar to substances of different density within a centrifuge? I envisage many instrumental lines following circular paths at different times. Instrumental lines progressively become fixed in their circular repetition like substances that become stuck on the outer edge of the centrifuge. There are potentially endless combinations of layering as all the melodic lines interact at different times.

I am in the process of discovering the wide range of possibilities that this material offers. It is my job now to discern its musical essence.

Composition Diary - June 2003

Since my last diary entry, I have been working solidly on my orchestral piece and I'm happy to report that it is practically finished. I still need to do some proofreading but all of the notes are now written down.

Throughout the composition of my piece, I have been working with the musical potential of a melody that follows a circular path. By composing an ensemble piece that experimented with the layering of this melody at different points, I determined, on the small scale, the structural framework for my orchestral work. The form is principally canonic, however, pairs of voices exist (specifically placed a quaver beat apart from each other) within the polyphony. Each voice articulates the melody in varying transpositions until it eventually returns to the tone centre from which it began (E). Having travelled full circle, it then ceases. Overall, this generates a kind of arch form where the layering of voices increases until a point of maximum density after which the layering of voices is seen to decrease.

In my orchestration of this canonic structure, I have been careful not to simply assign an instrumental line to a single voice. There exist specific gestures within the melodic idea that plead for characterisation. Therefore, at the start of the work, the first statement of the melody is heard broken up into several gestures played by different groups of instruments across the orchestra. As more voices enter, the variety of instrumental groups associated with each gesture increases. However, at the point of maximum density, the orchestration changes dramatically. Firstly, the counterpoint is confined to just the woodwind section, then the brass and finally the strings. Gradually more instruments begin to join the string section running counter to a thinning polyphonic texture. This leads to an orchestral unison of the last statement of the melody by the last remaining voice.

I have given my piece the title of Centrifugue. It represents an amalgam of the ideas that have influenced my creative process: centrifugal force, the function of a centrifuge, and polyphonic structure.

Composition Diary - August 2003

In my previous diary entries I described my composition process in terms of the conceptual/abstract ideas that helped generate a structural framework for the music; eventually finding realisation in the orchestral medium. Now, having completed my draft score, I have shifted focus to the practical aspects of the piece.

In the teleconference held with the tutors last week, we mainly discussed practical issues and suggestions were made with regard to certain details. I am currently revising the layout of my score so that, in general, the bars are larger and more easily visible to the conductor. What is more, I will probably end up enlarging (by photocopying) the page size to create a more workable score. Other practical matters brought to light include an expression mark which I will include with the tempo direction for conciseness; making bar numbers more visible; and changing some idealistic trombone glissandi. For this last issue, I have re-consulted my orchestration books and am hoping to meet up with a trombonist to further verify the mechanics.

The tutors made another suggestion regarding the cello and double bass parts in the very first gesture of the piece. They play a sustained note which begins fortepiano and crescendos to triple forte with a downward glissando. This is in unison with the trombones and rolled timpani. The tutors suggested that the cello and bass would carry more weight if they played tremolo on the sustained note. I have already amended this in the score.

For the weeks ahead, I will commence the parts extraction and continue to refine my score.

Composition Diary - January 2004

I was extremely pleased with the performance and rehearsal of my work throughout the ACOF week in Hobart. When I received the recording of the final performance last week, I was struck once more by the energy, enthusiasm, and sheer professionalism that the TSO players brought to the interpretation of my piece.

The rehearsals ran very smoothly under Ken's direction and the orchestra was able to concentrate on details such as the articulation of certain gestures. These included: 1) changing a tenuto to an accent marking on an important slurred gesture so that its character was expressed more clearly, 2) placing a short figure played by the second trumpet at the start of the piece an octave higher to achieve better intonation with the first trumpet, 3) changing a note in the first violins to a harmonic for easier fingering and clearer expression, and 4) exaggerating the effect of the fortepiano dynamic marked at the beginning of each glissando gesture.

For the last rehearsal and for the final performance, Ken brought the tempo up to the full speed and I was thrilled with the resulting sense of momentum that the music conveyed.

It was often hard in the rehearsal space to hear the right balance between the instruments of the orchestra. Listening to the recording, however, I was happy to hear every instrument in perfect relation with one another.

Overall, I thought the week was a terrific success! I really enjoyed listening to the other participants' works and learned a lot from the tutors' comments throughout the week.