Arpeggio quality

7sus4

The dominant suspended fourth — the 'So What' chord — puts a minor seventh under the classic sus4 shape, creating the most famous suspended sound in jazz. The fourth still wants to fall to the third, but the seventh adds forward motion, so the chord can either resolve into a dominant seventh or float indefinitely over a static vamp. It is essential vocabulary for funk, gospel and contemporary jazz, and one of the most satisfying shapes to arpeggiate slowly. Because the third is absent, the chord never declares major or minor. Listen for the fourth and seventh framing the fifth: that stacked-fourths sound is the whole atmosphere.