Module 2 — Major Scales, Scale Degrees, Key Signatures, and the Circle of Fifths
This module gives you the framework that makes keys stop feeling like unrelated collections of sharps and flats.
The main idea is simple:
A major scale is not “seven notes to memorize.” It is a fixed pattern of distances.
And once you understand that, key signatures and the Circle of Fifths become much less arbitrary.
2.1The major-scale formulaA major scale follows this pattern:2.2Why G major needs F♯Let's build a major scale from G using the same formula.2.3Now build D majorUse exactly the same pattern:2.4This is the Circle of FifthsStart from C and move upward by perfect fifths:2.5Going the other direction gives flatsMove down a fifth from C—or up a fourth:2.6Don't memorize the Circle as a picture yetFor now, memorize just these two chains.2.7Scale degrees now become meaningfulEvery major scale has seven positions.2.8In G majorG major:2.9The dominant is always degree 5In C:2.10The fourth behaves differentlyIn C:2.11Major chords built on scale degreesNow let's build a triad on every note of C major using only notes from the scale.2.12Let's prove it in G majorG major scale:2.13This is the connection between scales and chordsThis is a crucial mental shift.2.14Let's apply that to a melodySuppose the melody note is E.2.15The difference between a key and a chordThis is worth making completely clear.2.16Key signatures are compressed instructionsWhen sheet music has one sharp:2.17How to recognize a sharp key quicklyThere's a useful shortcut.2.18Flat-key shortcutFor flat major keys:2.19Your first transposition exerciseTake this melody:2.20Now transpose a chord progressionTake:2.21Ear exercise: I, IV, VChoose C major first.2.22Ear exercise: 7 → 1Play these pairs slowly:2.23Finger exercise: scales without speedDo not treat this as a virtuosity exercise.2.24A very useful practice: random degree findingPick a key.2.25Build chords by numberIn G major:2.26One subtle but important idea: accidentals have spellingAt the piano:2.27Why the Circle of Fifths matters beyond key signaturesThe Circle of Fifths is not just a memorization diagram.2.28Practical mini-projectTake a very simple melody you know by ear.•Homework for Module 2Play slowly:•Module 2 mini-testTry before reading the answers.