Lesson 56 · All 12 keys

Diminished Major 7th Chord Trainer

Learn how a Diminished major 7th chord is built one semitone-count at a time — a diminished triad (Lesson 11) with a major 7th on top, instead of the diminished 7th a diminished 7th chord (Lesson 14) uses — then put it to work with three MIDI exercises: playing all 12 diminished Major 7th chords around the circle of fourths, and 5 jazz plus 5 gospel chord progressions that show off its color, in every key.

How a Diminished major 7th chord is built

A Diminished major 7th chord — written °(maj7) (e.g. C°(maj7)) — is a 4-note chord: a diminished triad (Lesson 11) with a major 7th on top, instead of the diminished 7th a diminished 7th chord (Lesson 14) uses. Every °(maj7) chord — in any of the 12 keys — is built the exact same way, by counting semitones to the right from a root note:

  1. The starting note — this note names the chord.
  2. Count 3 semitones up from the root — the minor 3rd.
  3. Count 3 more semitones up from the 3rd (6 semitones from the root) — the diminished (lowered) 5th, the same 5th a diminished triad (Lesson 11) uses.
  4. Count 5 more semitones up from the 5th (11 semitones from the root) — the major 7th, instead of the diminished 7th a diminished 7th chord (Lesson 14) uses.
Example — C°(maj7): start on C, count 3 semitones right to reach E♭, count 3 semitones more to reach G♭, count 5 semitones more to reach B. C‑E♭‑G♭‑B is the C°(maj7) chord.
A diminished major 7th chord swaps in a major 7th where a diminished 7th chord (Lesson 14) would use a fully-diminished 7th — a rare, unsettled half-step clash against the 5th below it, usually reached only briefly as a passing chord in minor keys.

Try it: pick a root and build the chord step by step

Step 1 of 4
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Chord toneNoteSemitones from rootMIDI #

All 12 diminished Major 7th chords at a glance

ChordRootMinor 3rdDiminished 5thMajor 7th

This MIDI exercise plays all 12 diminished Major 7th chords, one after another, moving around the circle of fourths — each chord's root sits a perfect 4th (5 semitones) above the last one: C → F → B♭ → E♭ → A♭ → D♭ → G♭/F♯ → B → E → A → D → G → back to C. Every chord is played as a full 4-note Diminished major 7th chord (root, minor 3rd, diminished 5th, major 7th together).

Chord 1 of 12
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The 12 chords, in circle-of-fourths order

#ChordRootMinor 3rdDiminished 5thMajor 7th

Five jazz chord progressions built around the Diminished major 7th chord. Pick a progression and play it in one key or cycle through all 12.

Key of C
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Progression in C

DegreeChordNotes

Five gospel chord progressions built around the Diminished major 7th chord. Pick a progression and play it in one key or cycle through all 12.

Key of C
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Progression in C

DegreeChordNotes