3.3: Scale Degree Names
Scale degrees, though often referred to by numbers, also have names.
These names will be used throughout this text to refer to scale degrees, chords built on these scale degrees, and keys associated with these scale degrees.
Another way to understand why some scale degrees have “sub-” in their names is through the following example.
Notice that the subtonic is a whole step below the tonic, while the leading tone is only a half step below the tonic.