Minor seventh chord

A minor seventh chord (mm7) is a four-note seventh chord built from a minor triad with a minor seventh above the root, stacked in thirds as minor third, major third, minor third. In AP Music Theory it's one of the chord qualities you identify by ear and in notation under Topic 3.1.

What is Minor seventh chord?

A minor seventh chord is a seventh chord, meaning four distinct pitches stacked in thirds on adjacent lines or spaces. Its recipe is a root, a minor third, a perfect fifth, and a minor seventh above the root. You can also think of it in two layers. The bottom three notes form a minor triad, and then you add a minor seventh on top. That's why it's often labeled "mm7" (minor triad, minor seventh) or just "m7."

The fastest way to spell one is by interval stack from the bottom up: minor third, major third, minor third. So D minor seventh is D-F-A-C. The sound is mellow and unresolved at the same time. It has the dark color of a minor triad, but the seventh adds a gentle dissonance that wants to move somewhere. That "both/and" sound is exactly what you're listening for on aural identification questions.

Why Minor seventh chord matters in AP Music Theory

This term lives in Unit 3 (Music Fundamentals III: Triads and Seventh Chords), specifically Topic 3.1. It directly supports learning objective 3.1.A, which asks you to describe the quality of a chord in both performed music and notated music. The CED's essential knowledge (PIT-1.O.1) defines seventh chords as four-pitch chords stacked in thirds, and the minor seventh chord is one of the five qualities you have to tell apart by sight and by ear. It also matters beyond Unit 3 because the minor seventh quality is what you get on the supertonic (ii7) in major keys, one of the most common pre-dominant chords you'll analyze later in the course. Nail the quality now and Roman numeral analysis gets much easier.

How Minor seventh chord connects across the course

Half-diminished seventh chord (Unit 3)

These two share the same minor seventh on top, but the triads underneath differ. A half-diminished chord sits on a diminished triad (lowered fifth), while a minor seventh chord sits on a minor triad (perfect fifth). One accidental on the fifth is the entire difference, which is why notated questions love this pair.

Major seventh chord (Unit 3)

Same idea, opposite colors. A major seventh chord is a major triad plus a major seventh, so it sounds bright and dreamy. The minor seventh chord flips both ingredients to minor. Hearing the triad quality first, then the seventh, is the reliable two-step for telling them apart aurally.

Diminished triad (Unit 3)

Knowing your triad qualities is the foundation for seventh chords. If you can instantly hear or spell a minor triad versus a diminished triad, you've already done most of the work of separating a minor seventh chord from a half-diminished one.

Chord inversion (Unit 3)

A minor seventh chord doesn't have to have its root in the bass. When the third, fifth, or seventh is on the bottom, the notes may not look stacked in thirds anymore. You have to mentally restack the pitches to find the root before you can name the quality.

Is Minor seventh chord on the AP Music Theory exam?

Topic 3.1 questions test chord quality two ways: from notation (you see the chord and name its quality) and from performed music (you hear it and name its quality). Multiple-choice stems often describe a chord by its ingredients, like "a minor triad with a minor seventh added above the root," and ask you to name the quality, or they flip it and give the quality and ask for the interval structure. Watch for the classic trap built into questions like "which seventh chord has a major third, perfect fifth, and minor seventh?" That's a dominant seventh, not a minor seventh. The minor seventh chord has a minor third above the root. Aurally, listen in two stages: is the triad major or minor, and is the seventh major or minor? Minor plus minor equals the mm7 sound.

Minor seventh chord vs Half-diminished seventh chord

Both chords have a minor third and a minor seventh above the root, so they look and sound like cousins. The difference is the fifth. A minor seventh chord has a perfect fifth (minor triad + m7), while a half-diminished seventh chord has a diminished fifth (diminished triad + m7). On notated questions, check the fifth above the root before you commit to an answer. By ear, the half-diminished chord sounds noticeably more tense and unstable because of that tritone between the root and fifth.

Key things to remember about Minor seventh chord

• A minor seventh chord is a minor triad with a minor seventh added above the root, four notes total stacked in thirds.

• The interval stack from the bottom up is minor third, major third, minor third, so D minor seventh spells D-F-A-C.

• It supports learning objective 3.1.A, which means you have to identify it both in notation and by ear.

• Don't confuse it with the dominant seventh chord, which has a major third above the root instead of a minor third.

• The only difference between a minor seventh chord and a half-diminished seventh chord is the fifth: perfect versus diminished.

• In major keys, the chord built on the second scale degree (ii7) is a minor seventh chord, which makes this quality show up constantly in later harmonic analysis.

Frequently asked questions about Minor seventh chord

What is a minor seventh chord in AP Music Theory?

It's a four-note seventh chord made of a root, minor third, perfect fifth, and minor seventh, or more simply a minor triad with a minor seventh stacked on top. It's one of the seventh chord qualities tested in Unit 3, Topic 3.1.

Is a minor seventh chord the same as a dominant seventh chord?

No. A dominant seventh chord is a major triad plus a minor seventh (major third above the root), while a minor seventh chord is a minor triad plus a minor seventh (minor third above the root). The seventh matches, but the triad underneath is different.

How is a minor seventh chord different from a half-diminished seventh chord?

Only the fifth changes. The minor seventh chord has a perfect fifth above the root, and the half-diminished chord has a diminished fifth. Everything else (minor third, minor seventh) is identical, which is exactly why exam questions pit them against each other.

How do you spell a minor seventh chord?

Stack thirds from the root: minor third, then major third, then minor third. For example, A minor seventh is A-C-E-G, and D minor seventh is D-F-A-C.

How do I hear a minor seventh chord on the aural part of the exam?

Listen in two steps. First decide whether the triad sounds major or minor, then decide whether the seventh sounds major or minor. A minor seventh chord gives you minor on both counts, producing a dark but smooth, jazzy sound without the harsh tension of a diminished or half-diminished chord.