A7+9 (A7#9) altered chord
Altered A chord for piano presented by keyboard diagrams.
Explanation: The A7+9 alter the A9 by the change of one note. The chord name can also be written as A7#9 or A7(#9).
Theory: The A7+9 are identical with the A9 except that the major ninth is sharpenedThe tone is one half step higher.
Notes: A - C# - E - G - B#