Ab Diminished Triad

Chord Tones: Ab Diminished Triad

Symbol: dim, ° — Formula: 1-♭3-♭5

DegreeNoteFrequency (A=440, Equal)
1 Ab 415.305 Hz
♭3 B 493.883 Hz
♭5 D 293.665 Hz

Chord Notation

Notation TypeSymbol / Value
Lead Sheet SymbolAbdim
All Common Symbolsdim, °
Interval Formula1-♭3-♭5
Harmonic Categorydissonant

Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.

Inversions

InversionNotes (low to high)Bass NoteSlash Notation
Root Position Ab B D Ab Ab Diminished Triad
First Inversion B D Ab B Ab Diminished Triad/B
Second Inversion D Ab B D Ab Diminished Triad/D

Harmonic Function

The Ab diminished chord commonly functions as the submediant (♭VI) in C minor or subdominant in E♭ major. Its harmonic role varies by key — in major keys it provides stable harmonic grounding.

The diminished triad features a flat third and flat fifth, creating a tense, unstable sound. It occurs naturally on the seventh degree of the major scale and resolves strongly to the tonic.

Common Progressions

The Ab Diminished Triad frequently appears in these progression patterns (shown in Roman numeral notation relative to key):

Songs Featuring the Diminished Triad

Well-known songs where the Ab Diminished Triad — or this chord type — plays a prominent role:

Tuning Frequencies Across Temperaments

Frequencies shown at A=440 Hz. View full temperament data for any note.

NoteEqual Temp.PythagoreanJust Intonation
Ab 415.305 Hz 417.657 Hz 418.601 Hz
B 493.883 Hz 495.000 Hz 490.548 Hz
D 293.665 Hz 293.332 Hz 294.329 Hz

Scales Containing the Ab Diminished Triad

These scales include the Ab Diminished Triad as a diatonic or characteristic chord: