Harmony
Modulation: How a Key Change Is Confirmed
A modulation is not a chromatic chord; it is a new key confirmed by cadence. The routes into one, and how to read them off the page.
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Glossary
Articles
Fundamentals
Circle of Fifths Explained: Keys, Signatures, Changes
The circle of fifths organizes every key by signature and closeness. How to read it, memorize it, and use it for modulation and chord choice.
Harmony
Augmented Sixth Chords: Italian, French and German Types
Italian, French and German sixth chords: how each type is built, how they resolve to V, and their use in enharmonic modulation.
Harmony
Harmonic Sequences and Circle Progressions That Modulate
Descending fifths, ascending 5-6 patterns, Pachelbel loops: how sequences work, when they modulate, and how to write them.
Harmony
Secondary Dominants and How Tonicization Works
A secondary dominant makes any chord a temporary tonic. How to spell one, where it turns up, and what cancels the effect.
Fundamentals
Relative and Parallel Keys Explained: Major and Minor Partners
A major key has two close minor partners. The relative minor shares its key signature, the parallel minor shares its tonic, and each pair connects keys in a different way.
Harmony
Tritone Substitution: The subV7 Chord That Still Resolves
Replace any dominant with the dominant a tritone away: why subV7 works, how it smooths bass lines, and where jazz standards hide it.
Harmony
Borrowed Chords: Modal Mixture in Practice
Mixture borrows chords from the parallel mode. What the common borrowed chords do to a phrase, how they resolve, and where labelling fails.
Harmony
The Neapolitan Sixth Chord: Sound, Spelling, Resolution
The flat-II chord that darkens minor keys: how the Neapolitan sixth is built, voiced, resolved, and used from Bach to Schubert.
Form
Rondo Form: How Refrains and Episodes Structure a Movement
Rondo form alternates a returning refrain with contrasting episodes. Learn classical key plans, sonata-rondo hybrids, and why refrains return altered.
Tuning & Temperament
Equal Temperament: What It Costs and What It Buys
Twelve equal semitones solve the problem pure intervals create. The cost is small in fifths, large in thirds, and paid by every fixed-pitch instrument.
Music History
Romantic Chromaticism and the Expanding Tonic
Chromatic harmony widened a key without leaving it: the resources that do the work, the Tristan chord, and how to analyse it without over-labelling.