Questions: Seventh Chord Construction

Question 1

Which of the following correctly identifies the notes of a dominant seventh chord built on D?

• A. D–F♯–A–C♯ (D major triad plus a major seventh)
• B. D–F♯–A–C (D major triad plus a minor seventh)
• C. D–F–A–C (D minor triad plus a minor seventh)
• D. D–F♯–A♭–C (D augmented triad plus a minor seventh)

Answer: (B)

A dominant seventh chord is always a major triad plus a minor seventh. D major triad = D–F♯–A; the minor seventh above D is C (ten half-steps, not eleven). Option A is a major seventh chord (D–F♯–A–C♯), the most common confusion — adding a major seventh instead of a minor seventh produces a major-7 chord, which has a lush floating quality rather than the driving urgency of the dominant seventh.

Question 2

Why does the dominant seventh chord create such a strong pull toward resolution in tonal music?

• A. Its major triad quality creates brightness that naturally contrasts with the tonic chord
• B. It is built on the fifth scale degree, which by convention always resolves to the first
• C. It contains a tritone between its third and seventh, producing two simultaneous tension forces that resolve by half-step motion
• D. The minor seventh interval is inherently dissonant and must resolve upward by a half step

Answer: (C)

The tritone is the key. In G7 (G–B–D–F), the third (B) and seventh (F) form a tritone — the most unstable interval in Western harmony. B is the leading tone that pulls up to C; F pulls down to E. These two simultaneous half-step resolutions make the dominant seventh the most directional chord in tonal music. Convention (being built on scale degree 5) is a consequence of this acoustic pull, not the cause.

Question 3

A major seventh chord and a dominant seventh chord both use a major triad as their foundation.

• T. True
• F. False

Answer: True

Yes — both chord types start with a major triad. What distinguishes them is the quality of the added seventh: the major seventh chord adds a major seventh (e.g., Cmaj7 = C–E–G–B), while the dominant seventh chord adds a minor seventh (e.g., C7 = C–E–G–B♭). This single half-step difference dramatically changes the harmonic quality: the major seventh floats softly; the dominant seventh drives urgently toward resolution.

Question 4

The dominant seventh chord built on G in the key of C major is G–B–D–F♯.

• T. True
• F. False

Answer: False

The seventh above G in the key of C major is F♮ (a minor seventh — ten half-steps), not F♯ (a major seventh — eleven half-steps). G–B–D–F♯ would be a Gmaj7 chord. The dominant seventh chord is G–B–D–F. This is the single most common construction error: using a major seventh where a minor seventh is needed, which eliminates the tritone and with it the chord's directional pull.

Question 5

Explain why understanding a seventh chord's intervallic recipe (triad type + seventh quality) is more useful than memorizing the notes of each chord spelling.

Model answer: The intervallic recipe lets you build any seventh chord from any root without a lookup table. Once you know a dominant seventh is always 'major triad + minor seventh,' you can construct D7, B♭7, or F♯7 instantly by applying the recipe. It also explains why each chord type sounds as it does — the dominant seventh drives because of its tritone, the major seventh floats because its major seventh is a half-step from the octave. Memorized spellings break the moment you change key or encounter a chromatic context; the recipe works everywhere.

This is the difference between instrumental knowledge and declarative knowledge. The recipe is portable: it scales to all 12 roots, all four common seventh chord types, and arbitrary transpositions. More importantly, it preserves the 'why' — you understand the chord's sonic character in terms of its intervals, not just its letter names.