Overall, there are three main timbres to the piece: gamelan, electronic keyboards, and string trio (violin, viola, and cello). Every one of these three groups can be broken down further into either their diversely timbred constituents, the numerous electronic waves at their disposal, and history of (extended) technique(s) but, overall, those are the three major families.
With the gamelan ensemble functioning as an "orchestral tutti", the others function as soloists. The string trio could be said to represent the three characters in the scenario (Isabelle/violin, Harlequin/viola, Dr. Pale/cello) but this is perhaps more poetic than to be taken (musically) literally.
The two electronic keyboards (sampler/synths really) could be said to represent the synthesis of all the three timbral elements: electronic, acoustic, and digital sampling. The electronic element is obviously representative of the Doctor, his laboratory cum Operating Room and his sadistic experiments. They could also be said to represent the philosopher's stone itself, that alchemical agent which makes all things whole again, which can turn lead into gold, of in Harlequin's and Isabelle's case, the reunification of the duad. In technical terms, this is done musically through what are known as hocketing techniques (imbal in Java and kotekan in Bali), that is, the splitting up of a single melodic line between two (or more) instruments. It could be said that these interlocking techniques, frequent in medeival music as well as Indonesian music, are but a monophonic way of suggesting polyphony.
Finally, there is the lone gamelan soloist, perhaps (and I mean perhaps) representing the philosopher's stone itself, the single element having the power to unify all others. Musically, this is a multi-faceted stone in that the player (Raharja) is constantly changing instrumentation in an effort to balance out the sound.
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