An angklung is two or three bamboo tubes tuned in octaves, hanging loose in a lashed frame. Shake it and it sounds one pitch — only one, forever. A melody therefore needs a room full of people, each holding a single note and entering on cue.

This system takes that constraint literally. Tube lengths step down across a rack, so a scale reads as a bar chart in bamboo. The ground is cured awi wulung, dark and matte. Every surface is a part of an assembly, never a finished solo object.