WebeleonPillar · Music Theory
Music Theory
Harmony, melody, and rhythm in plain language — the why behind the music, written so it actually sticks.
15 articles
Theory
The four-chord loop: I–V–vi–IV
I–V–vi–IV is the most-used pop progression of the last sixty years — Let It Be, No Woman No Cry, With or Without You. Here is why it works and why the progression was never the song.
Theory
The rock cadence: I–♭VII–IV
Three major chords borrowed from outside the key — I, ♭VII, and IV — are the engine of rock harmony. Here is why the flat seven works, why it never resolves, and how to make it groove.
Theory
The turnaround: I–vi–ii–V and rhythm changes
The I–vi–ii–V turnaround is the second most-played progression in jazz, and its full form — rhythm changes — is the template behind dozens of standards. Here is why the vi chord becomes dominant, and how the Tadd Dameron substitution rewrites the bass line.
Theory
Dorian Mode: minor scale with a raised 6th
Dorian is natural minor with the sixth raised by a half step — in A, A B C D E F♯ G. That one change turns the minor iv chord into a major IV, which is the sound of the i–IV vamp in jazz, rock, and pop.
Theory
Seventh-chord arpeggios from one shape
Maj7, dominant 7, minor 7, and half-diminished arpeggios all derive from one shape on the fretboard. Learn the template, then lower the third, the seventh, and occasionally the fifth.
Theory
Harmonic minor: the scale with the gap in it
Harmonic minor is the natural minor scale with a raised seventh. That one change gives minor keys a real dominant chord — and gives the scale its signature gap, the augmented second.
Theory
Triad inversions on string sets
A triad inversion puts the third or the fifth in the bass instead of the root. On a three-string set the three inversions chain up the neck — and chaining them is the drill.
Theory
Mixolydian, practically: the major scale with a flat seven
Mixolydian is the major scale with a lowered seventh — C D E F G A B♭ in C. Here is why that one note makes it the sound of rock, blues, and any chord loop that never quite goes home.
Theory
Andalusian cadence, the chord progression
The Andalusian cadence is four chords walking downhill — i–♭VII–♭VI–V. Here is how each chord works, where you have heard it, and a few more minor-key moves to steal.
Theory
Borrowed chords: minor colors in a major key
How the parallel minor lends a major key four darker chords — iv, ♭VI, ♭VII and ♭III — what each one does emotionally, and the songs that lean on them.
Theory
ii–V–I everywhere: the progression hiding in your playlists
The ii–V–I is the most common cadence in Western harmony. Here is how it works in C, how to move it to any key by function, and where it keeps hiding.
Theory
A progression isn't a song
Four looping chords are one section of a song, not the song. What bars, phrases, repetition, and forms actually do — and how Homechord v3 came to model them.
Theory
An arpeggio is a chord taken apart
An arpeggio is just the notes of a chord played one at a time. Here is how to build one from a triad, name its tones, and find it on the fretboard.
Theory
Voice Leading in Four Parts
How to move four independent voices smoothly between chords — common-tone retention, contrary motion, and the small steps that keep a progression singable.
Theory
The Circle of Fifths, Practically
A working musician’s tour of the circle of fifths — reading key signatures, finding closely related keys, and using the wheel to plan modulations on the fly.