Bass should drive large, slow visual elements and highs should drive fine, fast detail for maximum AV coherence

The physical size and speed of a visual element should match the perceptual character of the frequency band driving it. Bass energy is felt as large, slow, weighty — so it should drive elements with comparable visual weight: overall brightness, global scale, cell size. High-frequency energy is perceived as fine, fast, bright — so it should drive high-resolution or fast-changing detail: kaleidoscope sides, hue shift, grain. Cross-wiring (bass to a rapidly flickering hue, highs to a slow zoom) is the single most common coherence failure in band-to-parameter design.

Examples

Bass (a.fft[0]) → .scale() pulse reads as physical weight. Highs (a.fft[3]) → .kaleid() sides changes symmetry with the brightness. Swapping them makes the heavy bass flicker the symmetry and the delicate highs swell the whole image — incoherent.

Assessment

Assign the four FFT bands to four visual targets so that band-element size agreement is satisfied. Justify each assignment.