Circle of Fifths

Goal
Understand how to use the Circle of Fifths to find the notes of a key.

Vocabulary
•    key = set of 7 notes derived through major scale interval formula
•    Circle of Fifths = chart representing all 12 keys and their relationships
•    key signature = label for a key based on which notes are ♭ or ♯

Essential Knowledge
•    Applying the major/minor scale interval formula to all 12 notes gives us 12 sets of 7 notes each. These sets of notes are the 12 keys represented in the Circle of Fifths.
•    Each key is named with a key signature, which tells us which notes are sharped/flatted. 
•    Music that only uses notes from one key sounds cohesive.

Tips
•    Moving clockwise in the Circle of Fifths, the new sharp in each key signature is a 5th (7 half steps) up from the previous sharp: F♯, C♯, G♯, D♯, A♯. The newly sharped note is always the 7th note of that key’s major scale.
•    Moving counterclockwise in the Circle of Fifths, the new flat in each key signature is a 5th (7 half steps) down from the previous flat: B♭, E♭, A♭, D♭, G♭. It’s also helpful that the first 4 flats in order spell the word “bead.” The newly flatted note is always the 4th note of that key’s major scale.

Fun Facts
•    Transitioning between keys is called modulation.