Dycon

Those are some pretty advanced harmonic theory concepts. Basically you can plot out all notes in two dimensions which creates a map of harmony. This is called the Tonnetz or Harmonic Lattice. North on this lattice is ‘pentamerous”. A note on the piano can have different identities on this lattice and pentamerous notes can be more melancholy. That is the case in Soul to Squeeze. I’m surprised by the depth and quality of that wiki article, honestly. It’s exactly correct.