About Caug7 — uncommon voicings
Caug7 is C, E, G# and Bb — with the fifth raised a semitone.
It sounds strained and chromatic. The raised fifth is heard as a ♭13 sitting a semitone above where it is going, so the chord pushes harder than a plain dominant.
Altered dominant — the pull of a 7, sharpened.
Also written C7#5, C+7 or C7(#5).
What these less common shapes are
How to use Caug7
Caug7 is a dominant with its tension raised, so it still points at — harder than a plain seventh does. A plain dominant has two voices a semitone from home; an altered one has four, because every altered tone is also sitting a semitone from a note of F. More voices leaning the same way is all "more tension" means here.
In a phrase:→→
The ii–V–I of F.
Voice by voice, Caug7 → . 3 voices move by a semitone, and one note is common to both chords. Every voice that moves at all moves by a semitone — the shortest distance there is, which is why the change sounds settled rather than sudden.
| In Caug7 | Moves | In F |
|---|---|---|
| C, the root | stays where it is | C, the fifth |
| E, the major third | rises a semitone | F, the root |
| G#, the sharp fifth | rises a semitone | A, the major third |
| Bb, the flat seventh | falls a semitone | A, the major third |
What to play over Caug7
Every note of Caug7 is in C whole tone and C altered.
Each of those is a page: the scale across the neck, and the chords it harmonises into — which is where Caug7 sits in it. Every scale.
Chords near Caug7
Change one note of Caug7 and you have (the flat seventh becomes the major seventh), (the sharp fifth becomes the fifth), (the sharp fifth becomes the fifth), (the sharp fifth becomes the flat fifth), (add the sharp ninth) or (drop the flat seventh).
Caug7 is an altered chord — a dominant seventh with its fifth or ninth moved. Altered dominant chords on every root.
The common shapes and the derived voicings come from different places, and both are explained in how this site is built.