Chord and FretC7alt — altered dominant
Notes in C7alt: C – E – G# – Bb – D#Formula: 1 – 3 – #5 – b7 – #9In the formula, the numbers count steps of the major scale starting from the note that names the chord; "b" lowers a half step, "#" raises one — and a slash names the bass note.
The 7alt is not a fixed chord but an instruction: keep the root, the third and the seventh, and alter the tensions (b9, #9, #11, b13). Nobody plays them all at once — you pick two, and the tension peaks right before the resolution.
The same chord on all four instruments
Where to use it: The last dominant before the return home, above all in a minor key; the signature of jazz.
Every region of the neck hides more shapes of C7alt. In Chord and Fret, you hear every shape strummed string by string, in each instrument's own voice; compare positions with their difficulty marked; and change the tuning — the shape rewrites itself. Start free. Unlock everything with Pro. Plays offline.
See the whole neck in Chord and Fret →Part of the Altered dominants family.