
Ben R. answered 01/12/20
UC Berkeley Music Grad, Specializing in Piano and Music Theory
In music, there is a chord called the Dominant Seventh chord, which in the key of C is the notes G, B, D, F. When played, this chord gives the expectation of resolving on C, major or minor. However, these same notes, can also be observed as a German augmented 6th chord. In this case, you are in the key of B minor, and you are using the chord to lead into the dominant of B (F#), with the augmented sixth enharmonically replacing the minor seventh. Same notes in the chord, completely different chord progressions.