Audio response
Input selects a frequency band. Output is the target range at strength 1; Ease smooths attack and release. LF/HF/Full describe defaults, not instrument isolation.
Ring radius expands and contracts selected complete caustic cells around their dark centres, not their bright junctions or the whole image. Output sets local radius excursion; Ease smooths attack and return. Keep base drift at 0 for stationary centres. Only closed cells are selected; overlapping pulse regions are skipped. Ring radius needs 3 s and three attacks; custom bands need 3 s to calibrate. This is an artistic response, not a physical sand simulation.