A♭aug: G♯/A♭ Augmented Piano Chord

Root position: either hand, fingers low note to high
Hand	Notes	Fingers
Right	A♭, C, E	1-3-5
Left	A♭, C, E	5-3-1

Scale degree, note, and interval measured from the root.
Degree	Note	Interval from root	Semitones
1	A♭	Perfect unison	0
3	C	Major third	4
♯5	E	Minor sixth	8

Construction

A♭ Augmented = Root + Major 3rd + Minor 6th = A♭, C, E

Note	Interval	Degree
A♭	Root	1
C	Major 3rd	3
E	Minor 6th	♯5

Fingering

Note	Key color	Right hand	Left hand
A♭	black	thumb (1)	little finger (5)
C	white	middle finger (3)	middle finger (3)
E	white	little finger (5)	thumb (1)

Right hand: thumb (1) on A♭, middle finger (3) on C, little finger (5) on E.

Left hand: little finger (5) on A♭, middle finger (3) on C, thumb (1) on E.

A♭ Augmented Inversions

Root position
A♭ – C – E
1st inversion (A♭aug/C)
C – E – A♭
2nd inversion (A♭aug/E)
E – A♭ – C

Key Signature

A Augmented chord is built from symmetrical or ambiguous intervals, so it doesn't belong to a single key and has no key signature of its own.

Chords in the Key of A♭ Major

These are the triads built on each degree of A♭ Major:

I — A♭ Major (major)

Degree	Numeral	Chord	Quality
1	I	A♭ Major	Major
2	ii	B♭ Minor	Minor
3	iii	C Minor	Minor
4	IV	D♭ Major	Major
5	V	E♭ Major	Major
6	vi	F Minor	Minor
7	vii°	G Diminished	Diminished

Same Notes, Other Names

The notes A♭ – C – E aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell the following:

C Augmented→E Augmented→

A♭ Augmented : Frequently Asked Questions

What notes are in A♭aug?

A♭aug contains A♭, C and E. The formula is 1, 3, ♯5.

How do you play A♭aug on piano?

Play A♭, C and E together. Right hand fingers 1, 3, 5; left hand 5, 3, 1. A♭ is a black key; C and E are white.

What are the inversions of A♭aug?

3 positions: root position A♭ C E, A♭aug/C, A♭aug/E.

What is the difference between A♭aug and A♭aug7?

Adds G♭. 3 of the notes are shared.

What is an easy A♭aug for small hands?

The root and third only voicing, A♭3 C4, spans 4 semitones or about 55 mm.

What are the frequencies of A♭aug?

From A♭3 at A440 in 12-TET: 207.65, 261.63, 329.63 Hz.

What is the set class of A♭aug?

Prime form (048), Forte 3-12, interval vector <000300>.

How do I transpose A♭aug to another key?

Keep the 1, 3, ♯5 formula on the new root. Caug is C, E, G♯; D♭aug is D♭, F, A.

Is G♯aug the same as A♭aug?

Enharmonically yes: the same piano keys and the same sound, spelled differently.

A♭ Augmented in detail

Exact

Every pitch class is present and nothing outside the chord is added.

Type	Notes	Semitones	Span	Omissions and additions	Set relation
Close, root position	A♭3 C4 E4	8	110 mm	none	identical
Close, first inversion	C4 E4 A♭4	8	110 mm	none	identical
Close, second inversion	E4 A♭4 C5	8	110 mm	none	identical
Open, fifth on top	A♭2 E3 C4	16	220 mm	none	identical

Reduced

A subset of the pitch classes: the identity is incomplete rather than altered.

Type	Notes	Semitones	Span	Omissions and additions	Set relation	Fit
Root and third only	A♭3 C4	4	55 mm	omits E	subset

Spans are measured centre to centre at a 165 mm octave (standard keyboard geometry).

Position	Bass note	Notes in order	Figured bass	Semitones	Span
Root position	A♭	A♭3, C4, E4	5/3	8	110 mm
First inversion: A♭aug/C	C	C4, E4, A♭4	6/3	8	110 mm
Second inversion: A♭aug/E	E	E4, A♭4, C5	6/4	8	110 mm

One position per chord tone in the bass. Spans are for close position: voiced inversions appear under Voicings.

Change one note

Chords a single note away, and what moving that note does.

Chord	Change	Formula	Common tones
A♭aug7	adds G♭	1 3 ♯5 ♭7	3
A♭	E becomes E♭	1 3 5	2
A♭maj7	E becomes E♭, G	1 3 5 7	2
A♭7	E becomes E♭, G♭	1 3 5 ♭7	2
A♭6	E becomes E♭, F	1 3 5 6	2
A♭add9	E becomes E♭, B♭	1 3 5 9	2
A♭m	C, E becomes C♭, E♭	1 ♭3 5	1
A♭dim	C, E becomes C♭, E♭♭	1 ♭3 ♭5	1
A♭sus2	C, E becomes B♭, E♭	1 2 5	1
A♭sus4	C, E becomes D♭, E♭	1 4 5	1

Frequencies

Note	MIDI	Frequency
A♭3	56	207.65 Hz
C4	60	261.63 Hz
E4	64	329.63 Hz

Reference pitch A440, 12-TET, close root position.

Set theory: prime form, Forte number, interval vector

Absolute pitch class set: {8, 0, 4}
Normal order: [0, 4, 8]
Prime form: (048)
Forte number: 3-12
Interval vector: <000300>

Pair	Interval	Semitones	Interval class
A♭ to C	Major third	4	4
A♭ to E	Minor sixth	8	4
C to E	Major third	4	4

Where these facts come from

Every value on this page is derived from the note formula for a augmented applied to the root A♭, using standard music theory. Nothing here is hand-entered per chord, so the notes, intervals, inversions and frequencies cannot drift out of agreement with each other. Pitches assume 12-TET at A440.

A♭ Augmented

Fingerings

A♭ Augmented: notes and degrees