A Diminished Scale (Half-Whole)

Notes in the A Diminished Scale (Half-Whole)

Degree Name Note Frequency (A=440)
1 Tonic A 440.000 Hz
♭2 Altered 2nd A♯ 466.164 Hz
♭3 Minor Mediant C 261.626 Hz
3 Major Mediant C♯ 277.183 Hz
♯4 Tritone D♯ 311.127 Hz
5 Dominant E 329.628 Hz
6 Major Submediant F♯ 369.994 Hz
♭7 Subtonic G 391.995 Hz

Interval Pattern

Formula: H-W-H-W-H-W-H-W
Step Interval Semitones From Note To Note
1 Half Step (H) 1 A A♯
2 Whole Step (W) 2 A♯ C
3 Half Step (H) 1 C C♯
4 Whole Step (W) 2 C♯ D♯
5 Half Step (H) 1 D♯ E
6 Whole Step (W) 2 E F♯
7 Half Step (H) 1 F♯ G
8 Whole Step (W) 2 G A

Chords Built on Scale Degrees

Degree Note Chord Quality
1 A A diminished diminished
♭2 A♯ A♯ diminished diminished
♭3 C C diminished diminished
3 C♯ C♯ diminished diminished
♯4 D♯ D♯ diminished diminished
5 E E diminished diminished
6 F♯ F♯ diminished diminished
♭7 G G diminished diminished

Key Signature

3 — The A key signature uses F♯, C♯, G♯.

A Diminished Scale (Half-Whole) in Practice

The A Diminished Scale (Half-Whole) uses the key signature of 3 sharps (F♯, C♯, G♯). A major has three sharps (F#, C#, G#) and a bright, clear sound. It is extremely common in popular music and rock, particularly on guitar, and is easily sung by most voices. On guitar, A positions offer open-string resonance for fingering positions for this scale.

The half-whole diminished scale alternates half and whole steps, creating an 8-note symmetrical scale ideal for dominant chord improvisation and tension-building in jazz. When played starting on A, the 8 notes are A, A♯, C, C♯, D♯, E, F♯, G. In this key the signature has 3 sharps (F♯, C♯, G♯). A is the universal tuning reference pitch (A440) and sits naturally on guitar, mandolin, and violin as an open string. Blues guitarists gravitate toward A because the open A string provides a driving bass note for shuffle rhythms and the standard blues box pattern sits comfortably in fifth position.

Tuning Frequencies Across Temperaments

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

Note Equal Temp. Pythagorean Just Intonation
A 440.000 Hz 440.000 Hz 436.043 Hz
A♯ 466.164 Hz 463.538 Hz 470.926 Hz
C 261.626 Hz 260.740 Hz 261.626 Hz
C♯ 277.183 Hz 278.437 Hz 279.067 Hz
D♯ 311.127 Hz 309.026 Hz 313.951 Hz
E 329.628 Hz 330.001 Hz 327.032 Hz
F♯ 369.994 Hz 371.251 Hz 367.911 Hz
G 391.995 Hz 391.111 Hz 392.438 Hz

Related Scales

Guitar: A Diminished Scale (Half-Whole) Positions

The A key offers 3 sharps (F♯, C♯, G♯) on guitar. Sharp-side keys like A are idiomatic guitar keys because open strings (E, A, D, G, B, E) align with the scale's natural resonance points.