D♭aug7: C♯/D♭ Augmented 7th Piano Chord

Root position: either hand, fingers low note to high
Hand	Notes	Fingers
Right	D♭, F, A, C♭	2-3-4-5
Left	D♭, F, A, C♭	5-4-3-2

Scale degree, note, and interval measured from the root.
Degree	Note	Interval from root	Semitones
1	D♭	Perfect unison	0
3	F	Major third	4
♯5	A	Minor sixth	8
♭7	C♭	Minor seventh	10

Construction

D♭ Augmented 7th = Root + Major 3rd + Minor 6th + Minor 7th = D♭, F, A, C♭

Note	Interval	Degree
D♭	Root	1
F	Major 3rd	3
A	Minor 6th	♯5
C♭	Minor 7th	♭7

Fingering

Note	Key color	Right hand	Left hand
D♭	black	index finger (2)	little finger (5)
F	white	middle finger (3)	ring finger (4)
A	white	ring finger (4)	middle finger (3)
C♭	white	little finger (5)	index finger (2)

Right hand: index finger (2) on D♭, middle finger (3) on F, ring finger (4) on A, little finger (5) on C♭.

Left hand: little finger (5) on D♭, ring finger (4) on F, middle finger (3) on A, index finger (2) on C♭.

D♭ Augmented 7th Inversions

Root position
D♭ – F – A – C♭
1st inversion (D♭aug7/F)
F – A – C♭ – D♭
2nd inversion (D♭aug7/A)
A – C♭ – D♭ – F
3rd inversion (D♭aug7/C♭)
C♭ – D♭ – F – A

Key Signature

A Augmented 7th 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 D♭ Major

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

I — D♭ Major (major)

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

Same Notes, Other Names

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

C♯ 7♯5→

D♭ Augmented 7th : Frequently Asked Questions

What notes are in D♭aug7?

D♭aug7 contains D♭, F, A and C♭. The formula is 1, 3, ♯5, ♭7.

How do you play D♭aug7 on piano?

Play D♭, F, A and C♭ together. Right hand fingers 2, 3, 4, 5; left hand 5, 4, 3, 2. D♭ is a black key; F, A and C♭ are white.

What are the inversions of D♭aug7?

4 positions: root position D♭ F A C♭, D♭aug7/F, D♭aug7/A, D♭aug7/C♭.

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

Drops C♭. 3 of the notes are shared.

What is an easy D♭aug7 for small hands?

The guide tones, 3 and ♭7 voicing, F3 C♭3, spans 6 semitones or about 83 mm.

What are the frequencies of D♭aug7?

From D♭3 at A440 in 12-TET: 138.59, 174.61, 220.00, 246.94 Hz.

What is the set class of D♭aug7?

Prime form (0248), Forte 4-24, interval vector <020301>.

How do I transpose D♭aug7 to another key?

Keep the 1, 3, ♯5, ♭7 formula on the new root. Caug7 is C, E, G♯, B♭; Daug7 is D, F♯, A♯, C.

Is C♯aug7 the same as D♭aug7?

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

D♭ Augmented 7th 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	D♭3 F3 A3 C♭3	10	138 mm	none	identical
Close, first inversion	F3 A3 C♭3 D♭4	8	110 mm	none	identical
Close, second inversion	A3 C♭3 D♭4 F4	8	110 mm	none	identical
Close, third inversion	C♭3 D♭4 F4 A4	10	138 mm	none	identical
Drop 2	A2 D♭3 F3 C♭3	14	193 mm	none	identical
Drop 3	F2 D♭3 A3 C♭3	18	248 mm	none	identical
Drop 2 and 4	D♭2 A2 F3 C♭3	22	303 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
Shell, root ♭7 3	D♭2 C♭2 F3	16	220 mm	omits A	subset
Guide tones, 3 and ♭7	F3 C♭3	6	83 mm	omits D♭ and A	subset
Rootless close	F3 A3 C♭3	6	83 mm	omits D♭	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	D♭	D♭3, F3, A3, C♭3	7	10	138 mm
First inversion: D♭aug7/F	F	F3, A3, C♭3, D♭4	6/5	8	110 mm
Second inversion: D♭aug7/A	A	A3, C♭3, D♭4, F4	4/3	8	110 mm
Third inversion: D♭aug7/C♭	C♭	C♭3, D♭4, F4, A4	4/2	10	138 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
D♭aug	drops C♭	1 3 ♯5	3
D♭7	A becomes A♭	1 3 5 ♭7	3
D♭9	A becomes A♭, E♭	1 3 5 ♭7 9	3
D♭	A, C♭ becomes A♭	1 3 5	2
D♭maj7	A, C♭ becomes A♭, C	1 3 5 7	2
D♭m7	F, A becomes F♭, A♭	1 ♭3 5 ♭7	2
D♭m7♭5	F, A becomes F♭, A♭♭	1 ♭3 ♭5 ♭7	2
D♭7sus4	F, A becomes G♭, A♭	1 4 5 ♭7	2
D♭6	A, C♭ becomes A♭, B♭	1 3 5 6	2
D♭add9	A, C♭ becomes A♭, E♭	1 3 5 9	2

Frequencies

Note	MIDI	Frequency
D♭3	49	138.59 Hz
F3	53	174.61 Hz
A3	57	220.00 Hz
C♭3	59	246.94 Hz

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

Set theory: prime form, Forte number, interval vector

Absolute pitch class set: {1, 5, 9, 11}
Normal order: [9, 11, 1, 5]
Prime form: (0248)
Forte number: 4-24
Interval vector: <020301>

Pair	Interval	Semitones	Interval class
D♭ to F	Major third	4	4
D♭ to A	Minor sixth	8	4
D♭ to C♭	Minor seventh	10	2
F to A	Major third	4	4
F to C♭	Tritone	6	6
A to C♭	Major second	2	2

Where these facts come from

Every value on this page is derived from the note formula for a augmented 7th applied to the root D♭, 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.

D♭ Augmented 7th

Fingerings

D♭ Augmented 7th: notes and degrees