What Is a Chord Progression? Music Theory Explained

What Is a Chord? What Is a Progression?

A chord is three or more notes played simultaneously. The most fundamental chord type is a triad — a root note, a third, and a fifth. Stack a major third above the root followed by a minor third, and you get a major chord: bright, stable, resolved. Flip those intervals — minor third first, then major third — and you get a minor chord: darker, more introspective. From these two basic types, an enormous harmonic vocabulary opens up.

A progression is simply those chords placed in sequence, one following the next in a way that creates a sense of movement. Harmony in music isn't static — it moves forward, builds tension, and then resolves (or deliberately refuses to resolve). That push-and-pull of tension and resolution is what chord progressions control.

Progressions are typically described using Roman numerals that indicate each chord's position in a scale. In the key of C major, C is the I chord, D minor is the ii chord, E minor is the iii, F is the IV, G is the V, A minor is the vi, and B diminished is the vii°. This notation works across all 12 keys — so when you learn a progression as I–V–vi–IV, you know it in every key without having to relearn it.

The Nashville Number System

The Nashville Number System is a simplified version of Roman numeral notation widely used in session work and songwriting. Chords are simply numbered 1 through 7, with minor chords marked with a minus sign (1, 2-, 3-, 4, 5, 6-, 7°). A session player who knows the "1–5–6–4" can play it immediately in whatever key the artist is in. It's a fast, key-agnostic shorthand that every producer benefits from knowing.

Common Chord Progressions Every Producer Should Know

Certain progressions appear across decades and genres because they work — not because musicians lack imagination, but because these harmonic movements tap into something deeply intuitive about how human ears process tension and resolution.

I–V–vi–IV (The "Four Chord" Progression)

In C major: C – G – Am – F. This is the most widely used chord progression in modern popular music — it underpins thousands of pop, rock, and country songs. Its power is in its balance: the V creates mild tension, the vi introduces a reflective, minor-tinged color, and the IV resolves things back before the I closes the loop. It works in both major and minor contexts and sounds equally convincing at almost any tempo.

ii–V–I (Jazz Fundamental)

In C major: Dm7 – G7 – Cmaj7. The ii–V–I is the backbone of jazz harmony. The ii chord sets up mild tension, the dominant V chord creates strong tension (especially with its tritone interval), and the I chord resolves it cleanly. Jazz extended this idea in every possible direction — adding extensions, substitutions, and alterations — but the basic ii–V–I is where it all starts. This progression is also widely used in neo-soul and lo-fi hip-hop, often with extended voicings (9ths, 11ths, 13ths).

vi–IV–I–V (Minor-First Variation)

In C major: Am – F – C – G. Starting on the vi chord instead of the I gives the same underlying harmony a darker, more introspective feel. This is extremely common in pop and singer-songwriter music — it begins in a minor emotional space and doesn't fully resolve until the very end of the loop. Many tracks that feel wistful or melancholic use this starting point.

i–VII–VI–VII (Natural Minor Loop)

In A minor: Am – G – F – G. A pure minor key loop with no raised leading tone — the VII chord stays flat, giving the progression a modal, slightly unresolved quality. Common in dark hip-hop, trap, and cinematic music. The absence of a strong dominant resolution is part of what gives it that brooding, unsettled character.

I–IV–V–IV (The Blues Turnaround)

In C major: C – F – G – F. The core of blues and rock harmony, often extended into a 12-bar structure. Simple, powerful, and endlessly adaptable. The IV–V–IV movement at the end creates a gentle turnaround that pulls naturally back to the I.

I–vi–IV–V (The '50s Progression)

In C major: C – Am – F – G. Ubiquitous in doo-wop, early rock and roll, and retro-influenced pop. The vi chord introduces a moment of minor color before the IV–V movement drives the progression forward with purpose. Nostalgic-sounding by modern ears, but still in active use in lo-fi and bedroom pop.

Major vs. Minor: How Key Shapes Emotion

Whether a progression is built in a major or minor key shapes its emotional baseline before you've even written a melody. This isn't a rule — it's a tendency, and genre context matters enormously — but it's a useful starting framework.

Major keys tend to sound brighter, more resolved, and emotionally open. Major chord progressions are used for uplift, happiness, triumph, and accessibility. The I, IV, and V chords in a major key are all major triads, which reinforces that stable, consonant character.

Minor keys tend to sound darker, more introspective, and emotionally complex. The i, iv, and v chords in a natural minor key are all minor triads (with the v being minor rather than dominant), which gives the harmony a heavier, more melancholic weight. Raising the seventh scale degree to create a harmonic minor scale introduces a classical leading tone that creates strong tension before the i chord.

A key concept here is that the same chord can function differently depending on context. An A minor chord at the start of a vi–IV–I–V loop feels wistful. The same A minor chord in the middle of a jazz ii–V–I substitution feels entirely different. Progressions create meaning through movement and context, not just from the individual chords.

How Chord Progressions Create Emotion

The emotional impact of a chord progression comes from three sources: tension and resolution, interval relationships, and expectation and surprise.

Tension and Resolution

The dominant chord (V or V7) creates strong tension because it contains a tritone — the most dissonant interval in Western harmony — which wants to resolve to the tonic. When that resolution arrives on the I chord, listeners feel release. This is the push-pull mechanism underlying virtually all harmonic movement in Western music. A progression that resolves cleanly feels satisfying; a progression that avoids resolution creates suspense, nostalgia, or unease.

Voice Leading

Voice leading is the movement of individual notes within a chord as it changes to the next chord. Good voice leading keeps each note moving by the smallest interval possible — often just a half step or whole step — rather than leaping large distances. This creates smooth harmonic motion that sounds natural and coherent. In the piano roll of your DAW, you can see voice leading directly: the notes in each chord should trace smooth paths rather than jumping wildly between chords.

Extensions and Color

Adding notes beyond the basic triad changes a chord's emotional color without changing its function. A Cmaj7 has a dreamy, suspended quality that a plain C major doesn't. A minor 9th chord has a sophisticated melancholy that a plain minor chord lacks. Lo-fi and jazz production leans heavily on extended chords (7ths, 9ths, 11ths, 13ths) for exactly this reason — they add warmth and complexity to simple progressions.

Why Producers Use MIDI Chord Packs

Writing chord progressions from scratch requires music theory knowledge, an instrument, and time. MIDI chord packs short-circuit that process: you get a library of progressions — already voiced, already in all 12 keys — that you can audition immediately and customize from there. It's not about avoiding music theory; it's about spending your production time building and arranging rather than hunting for the right chord voicing. Most producers using MIDI packs are also learning theory in the process, simply by looking at what's in the piano roll.