On a nostalgic whim, I was playing around learning this piece of music from Final Fantasy 7, as I was interested in the chord changes that happen (specifically, the first two chords in the tune).
What's going on here? From what I've figured out on the piano, it starts out in Fmaj (might not be F, haven't got perfect pitch), and then seems to go to a Bbmin before going back to Fmaj again.
But the "correct" chord in F major is Bbmaj. Is this simply a temporary key change for this chord? I'm aware of parallel modulation, but is there something special about using the subdominant chord to do this? If this isn't parallel modulation, what is it?