The diminished triad arpeggio stacks two minor thirds — root, ♭3 and ♭5 — a tense shape used to lead between chords.
The diminished triad arpeggio stacks two minor thirds — root, ♭3 and ♭5 — a tense shape used to lead between chords. On guitar, the a diminished arpeggio uses the notes A, C, D♯ — the diagram above shows every one of them across all positions of the neck, with the root (A) highlighted so you can anchor each shape.
KnowYourNeck turns this into an interactive neck you can rotate through every position, switch between note names and scale degrees, and drill one box at a time with Focus Mode. It's the fastest way to actually learn the diminished arpeggio instead of just reading a chart.