Reference

Four reference pages that the other sections lean on: interval arithmetic, the relations between keys, key signatures, and the number system used to write a chord chart that survives a change of key.

• ReferenceIntervals12 intervals, with compound extensions
• ReferenceCircle of fifths12 keys, relative minors, order of accidentals
• ReferenceKey signatures15 major keys, 15 minor keys
• ReferenceNashville number systemdegrees 1-7 in all 12 keys

How the pages relate

• Intervals gives the distances. Every other page on this site is built from them.
• Circle of fifths places the twelve keys in order of their accidentals.
• Key signatures lists the accidentals of each key, including the three enharmonic signatures that do not appear elsewhere on the site.
• Nashville number system names the chords of a key by degree, which is the same information as the chord families listed on each key page.

Related

• ReferenceIntervals12 intervals, with compound extensions
• ReferenceCircle of fifths12 keys, relative minors, order of accidentals
• ReferenceKey signatures15 major keys, 15 minor keys
• ReferenceNashville number systemdegrees 1-7 in all 12 keys
• CapoCapo chart12 capo positions × 24 target keys
• KeyKey of CC D E F G A B · C major / A minor
• HubCapo referencecapo 1 to 12, all target keys
• HubChords12 roots × 23 qualities

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Section: Reference · Theory Atlas