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Db7 — Db dominant seventh chord

A major triad with a minor seventh added. The interval between the third and the seventh is a diminished fifth, which is unstable and wants to resolve inwards.

Symbol
Db7
Root
Db
Quality
Dominant seventh
Family
seventh
Notes
Db F Ab Cb
Degree formula
1 3 5 b7
Semitones from the root
0 4 7 10
Distinct pitch classes
4
Interval structure
Stacked from the root: 4 semitones, 3 semitones, 3 semitones
Notation
Written 7. The chord on the fifth degree of a key, and the standard blues chord.
Key
Db · Db major / Bb minor key signature

Formula

The chord tones in order from the root, with the interval each one forms above it.

DegreeNoteSemitonesInterval from the root
1Db0Perfect unison
3F4Major third
5Ab7Perfect fifth
b7Cb10Minor seventh

Inversions

An inversion is the same set of notes with a different one in the bass. The last column gives the distance of each note above the bass note, in semitones.

InversionBass noteDegree in the bassNotes above the bassSemitones above the bass
root positionDb1Db – F – Ab – Cb0 4 7 10
first inversionF3F – Ab – Cb – Db0 3 6 8
second inversionAb5Ab – Cb – Db – F0 3 5 9
third inversionCbb7Cb – Db – F – Ab0 2 6 9

Playable voicings

These shapes were found by searching the fretboard of a standard-tuned guitar (E A D G B E) rather than copied from a chord book. The search allows every string to sound or to be muted, rejects any shape with a muted string between two sounding strings, rejects any shape whose fretted notes span more than four frets (a five-fret window), requires every chord tone to be present, and then sorts what remains with root-position shapes first and the most compact, lowest shapes next. The shapes shown are the first six of that ordering; other orderings are possible at the same frets.

#Shape (low string first)NotesDegreesBassSpan (frets)Sounding strings
19-8-9-10-9-9Db F B F Ab Db1 3 b7 3 5 1Db26
29-11-9-10-9-9Db Ab B F Ab Db1 5 b7 3 5 1Db26
39-8-6-6-6-7Db F Ab Db F B1 3 5 1 3 b7Db36
49-8-6-6-9-7Db F Ab Db Ab B1 3 5 1 5 b7Db36
59-8-9-6-9-7Db F B Db Ab B1 3 b7 1 5 b7Db36
69-8-9-6-9-9Db F B Db Ab Db1 3 b7 1 5 1Db36

Shape numbers run from the lowest string to the highest, so the left-hand number is the sixth string (low E) in standard tuning. Multiple shapes are listed because a chord can be voiced several ways, and because a lower position is not always the better sounding one.

Related chords and scales

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