F minor - Research on Harmony - Variation 4

Variation 4 reaches Ab7 but carries the most shadows of the Ab7 valleys — 45%. Where Variation 2 was 72% highlights and Variation 3 was 52%, Variation 4 tips toward darkness: 45% shadow, 12% midtone, 43% highlight. The same extreme high register, but the lower portion of the phrase drags the palette down.

Seven notes: F2, C3, Ab3, F4, Ab5, Ab6, Ab7. The F and Ab's are distributed across many registers — three Ab's ascending through Ab3, Ab5, Ab6, Ab7, with C3 and F2 at the bass. The ascending cluster of Ab's builds blue through four registers before reaching near-white.

The tension is the shadows — nearly half the canvas is dark despite the silver apex. The four Ab's staircase is blue's fullest statement in the series: the minor third voiced at every available level, each step paler than the last.