B7#9

— About this chord

B7#9 (1–3–5–♭7–♯9), the classic “Hendrix chord,” clashes the major third against a raised ninth for a gritty, funky, blues-rock snarl. A cornerstone of funk, rock, and blues-rock rhythm playing, it also spices up soul and fusion vamps. On guitar it's an iconic compact shape near the open position; keyboardists use it for dirty dominant color. Functions as an altered V7, driving hard toward the tonic with attitude. Also searched as B7sharp9, B7(#9).