A Augmented (Aaug)
1+3+#5
Notes in A Augmented
A (root)C#E#
Inversions
Same notes as A Augmented, with a different chord tone as the lowest note. Useful for smoother movement between chords instead of jumping around the keyboard.
Root position
A in the bass
1st inversion
C# in the bass
2nd inversion
E# in the bass
Press A, C# and E# together on the keyboard and you're playing A Augmented.
Stretch the fifth of a major chord up by a semitone and the result is symmetrical: two identical major thirds stacked on top of each other. That symmetry means the chord has no clear sense of up or down, giving it a floating, slightly dizzying quality composers reach for when a moment needs to feel suspended or unresolved.