Chords
C# Dominant seventh
C# · E# · G# · B
The dominant seventh — a major triad with a minor seventh. The chord that creates the pull home.
Also written C#dom
C# Dominant seventh
C# · E# · G# · B
Voicings on the piano
| Voicing | Notes | Play it on your instrument |
|---|---|---|
| Closed, root position | C#3 · E#3 · G#3 · B3 | |
| Open (drop 2) | G#2 · C#3 · E#3 · B3 | |
| Shell | C#3 · E#3 · B3 | |
| Rootless | E#3 · A#3 · B3 · D#4 |
Tap a key or a fret to hear it.
Anatomy
C# Dominant seventh (C#7) contains the notes C# · E# · G# · B, each with a role measured as an interval from the root.
Read on: how triads are built · seventh chords
Inversions
An inversion of C# Dominant seventh puts a chord tone other than C# in the bass; the name after the slash is that bass note.
Where it lives
The keys and the scales C# Dominant seventh belongs to.
In which keys
C# Dominant seventh is diatonic to 3 keys; the numeral is its degree and the label its harmonic function.
Scales that contain it
C# Dominant seventh fits inside these scales, each built on C#.
- C# MixolydianC# · D# · E# · F# · G# · A# · B
- C# Phrygian DominantC# · D · E# · F# · G# · A · B
- C# Mixolydian PentatonicC# · E# · F# · G# · B
- C# Mixolydian b6C# · D# · E# · F# · G# · A · B
- C# BebopC# · D# · E# · F# · G# · A# · B · B#
- C# Spanish HeptatonicC# · D · E · E# · F# · G# · A · B
- C# Bebop MinorC# · D# · E · E# · F# · G# · A# · B
- C# Kafi RagaC# · E · E# · F# · G# · A# · B · B#
Understanding the C# Dominant seventh chord
Names and symbols
C#7 is the chord symbol for C# Dominant seventh; it is also written C#dom.
C# Dominant seventh and Db Dominant seventh are the same sound spelled two ways; both have a page here, and each links to the other. Db Dominant seventh
How it is built
On C# it is C# · E# · G# · B, stacking 1P · 3M · 5P · 7m. The major triad supplies stability and the minor seventh supplies tension.
Inside it, the third and the seventh are a tritone apart. That tritone is the entire engine: the third wants to rise a semitone and the seventh to fall a semitone, and where they land defines the key.
How it is used
As the V7 of a key it is the strongest possible signal of where home is. As the I7 and IV7 of a blues it loses that obligation entirely and simply becomes the sound — twelve-bar blues is built from dominant sevenths that never resolve conventionally.
Because its tritone is shared with the dominant seventh a tritone away, C#7 can be substituted for that chord and still resolve convincingly. That is tritone substitution, and it is how a chromatic bass line gets built.
Learn this properly
Chapter 10: Chords: Triads and SeventhsCommon questions
- What notes are in C#7?
- C#7 contains C# · E# · G# · B. Name any set of notes with the chord identifier.
- Why does a dominant seventh want to resolve?
- Its third and seventh form a tritone. The third rises and the seventh falls by a semitone each, closing onto the tonic chord.
- What is tritone substitution?
- Replacing a dominant seventh with the one a tritone away. Both contain the same tritone, so both resolve to the same place — but the substitute moves the bass down a semitone instead of a fifth.
- What notes are in the C# Dominant seventh chord?
- The C# Dominant seventh chord contains the notes C# · E# · G# · B: the root C# with the intervals 1P, 3M, 5P, 7m stacked above it. Play them together for the chord or one after another for an arpeggio. The lowest note is normally C#, but any chord tone can take the bass in an inversion.
- What intervals make up the C# Dominant seventh chord?
- Measured from C#, the C# Dominant seventh chord stacks the intervals 1P, 3M, 5P, 7m. The quality of the third and of the seventh, if there is one, is what gives the chord its character; the rest of the notes colour it. Every interval in the formula links to its own page, with its sound.