A diminished triad uses 0, 3, 6 semitones. An augmented triad uses 0, 4, 8. Compare their interval structure.
Diminished triad
Sounding pitches: D4 · F4 · G#4
Hear how the outer span changes: diminished uses two stacked minor thirds; augmented uses two stacked major thirds.
Diminished triad: root D4, bass D4; sounding notes D4, F4, G#4. Semitone offsets: 0, 3, 6.
Augmented triad
Sounding pitches: D4 · F#4 · A#4
Compare the compact 0–3–6 structure with 0–4–8. Both the middle and upper members change in this pair.
Augmented triad: root D4, bass D4; sounding notes D4, F#4, A#4. Semitone offsets: 0, 4, 8.
For aural examples, sounding pitch names are a listening reference. Written-note exercises preserve the displayed spelling.
Check the idea: The diminished outer span is six semitones; the augmented outer span is eight.
Listen for the narrower or wider outer span, then connect it to the quality label.
Choose diminished or augmented across changing roots. Use the sounding notes in feedback to inspect the structure after answering.
Identify the fresh sonorities without assuming that a change of register changes the chord quality.
Each session starts with two guided questions, then your chosen practice set, followed by two new questions at a different tempo. First answers, same-question retries, and the final check have separate results.
Begin this lesson90 quarter-note BPM · 4/4 · With guidance
Diminished triad, Augmented triad
Practice this level95 quarter-note BPM · 4/4 · Fewer hints
Diminished triad, Augmented triad
Practice this level100 quarter-note BPM · 4/4 · Fewer hints
Diminished triad, Augmented triad
Practice this levelThe teacher pack includes 10 fixed questions, replay controls, a student sheet, and a separate answer key. The printed key and downloaded JSON use the same questions.
Original synthesized audio · A4 = 440 Hz · mono, 48 kHz WAV.
These references explain the underlying definitions. The examples and practice sequences here are generated for Earstep.