Phrygian Vamp

The Phrygian mode's signature is the ♭2 — the one note that distinguishes Phrygian from ordinary natural minor. The classic voicing puts a ♭II major triad on top of the i bass. For Cm Phrygian: D♭/Cm. The D♭ triad's three notes (D♭, F, A♭) supply the ♭9, 4, and ♭13 of the minor i — all the Phrygian tensions in one familiar major-triad shape.

Both hands play whole notes. The ♭II is a half-step above the tonic, which gives the chord its Spanish quality — that half-step is what makes flamenco sound flamenco. Vamps don't modulate; the mode is the destination, not the journey.