Lesson 37 · All 12 keys

Dominant 7♭5 Chord Trainer

Learn how a Dominant 7♭5 chord is built one semitone-count at a time — a plain dominant 7th chord (Lesson 13) with its 5th lowered a semitone — then put it to work with three MIDI exercises: playing all 12 Dominant 7♭5 chords around the circle of fourths, and 5 jazz plus 5 gospel chord progressions that show off its color, in every key.

How a Dominant 7♭5 chord is built

A Dominant 7♭5 chord — written 7♭5 (e.g. C7♭5) — is a 4-note chord: a plain dominant 7th chord (Lesson 13) with its 5th lowered a semitone. Every 7♭5 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 4 semitones up from the root — the major 3rd.
  3. Count 2 more semitones up from the 3rd (6 semitones from the root, instead of the usual 3) — the ♭5th, a perfect 5th lowered a semitone.
  4. Count 4 more semitones up from the ♭5th (10 semitones from the root) — the minor 7th, the same 7th a plain dominant 7th chord uses.
Example — D♭7♭5: start on D♭, count 4 semitones right to reach F, 2 more (6 from the root) to reach G, then 4 more to reach C♭ (B natural). D♭‑F‑G‑C♭ is the D♭7♭5 chord.
A ♭5 alteration makes a dominant 7th chord symmetric under tritone substitution: the root and ♭5th of a 7♭5 chord sit exactly a tritone (6 semitones) apart, so C7♭5 and G♭7♭5 share the exact same four notes, just spelled from a different starting point. That's why this chord is a favorite for jazz pianists exploring tritone substitutions — swapping a V7 for the dominant chord a tritone away.

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 Dominant 7♭5 chords at a glance

ChordRoot+4 semitones → Major 3rd+2 semitones → ♭5th+4 semitones → Minor 7th

This MIDI exercise plays all 12 Dominant 7♭5 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 Dominant 7♭5 chord (root, major 3rd, ♭5th, minor 7th together).

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

#ChordRootMajor 3rd♭5thMinor 7th

Five jazz chord progressions built around the Dominant 7♭5 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 Dominant 7♭5 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