BookatlasPiano Rabbit Hole: Improvisation Theory & Practice
4355 / 18210 · Workshop 26 — “’Round Midnight”: Chromatic Melody, Diminished Color, Altered Dominants, and Making Dissonance Sound Beautiful← prev⊞ allnext →

26.36Level 10 — ♯9 color

G7♯9 contains:

A♯/B♭.

In jazz spelling/context, this is the altered 9.

So the chord can contain:

B natural = 3

B♭ = ♯9 sound.

That major/minor-third proximity is highly tense.