C#aug7 guitar chord
An open string left ringing against a fretted grip. Because it costs no finger, it sounds a note the closed shape has none left for -- a tension on top, or a pedal root underneath. Either a familiar grip with open strings added, or a shape so sparse the open strings carry the chord. These belong to their key rather than to a shape, so D, A, G and E have many and Eb a handful.
- Tap a note to hear it
- Arrows change position
- Fingers, notes or intervals
- Play the chord
About C#aug7 — open string voicings
C#aug7 is C#, E#, A and B — C#7 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.
C#aug7 notes and formula
| C# | E# | A | B |
|---|---|---|---|
| 1 | 3 | ♯5 | ♭7 |
Altered dominant — the pull of a 7, sharpened.
Also written C#7#5, C#+7 or C#7(#5). The same chord either way; which spelling you meet depends on who wrote the chart.
How to play C#aug7
An open string left ringing against a fretted grip. It costs no finger, so it can sound a note the closed shape has none left for: a tension on top, or a pedal root underneath.
These belong to their key rather than to a shape: they cannot be moved up the neck. D, A, G and E have many; E♭ has a handful.
C#aug7 has 6 of them, on strings 5-4-3-2-1, strings 6-5-4-3-2-1 and strings 6-4-3-2-1, from the 2nd fret up to the 6th — every inversion the chord has: C# in the bass, G## in the bass and B in the bass. The one to learn first is the B shape at the 2nd fret, which is the easiest grip here.
3 of them sit on strings 5-4-3-2-1, so you can run the inversions up one set without changing strings — which is the whole reason to learn them as a family rather than as separate grips.
Start with x43201 — 1 open string and down at the nut. 1 of the 7 shapes here sits in open position. None of them needs a barre. Together they cover the neck from the 1st fret to the 14th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| x43201 | open position | C#, root position | E# | 1 open string |
| x434x5 | 3rd fret | C#, root position | A | all fretted |
| x47465 | 4th fret | C#, root position | A | all fretted |
| 987x07 | 7th fret | C#, root position | B | 1 open string |
| 9-8-9-x-10-x | 8th fret | C#, root position | A | all fretted |
| 9-x-9-10-10-x | 9th fret | C#, root position | A | all fretted |
| x-x-11-14-12-13 | 11th fret | C#, root position | E# | all fretted |
The same notes rebuilt from scratch give 2 shell, 13 drop 2 and 9 drop 3 voicings, each on its own page.
Tensions. A shell of C#aug7, root, third and seventh, leaves a string free, and the tones that belong over it are the b9 (D), the 9 (D#), the #9 (D##) and the #11 (F##).
How to use C#aug7
C#aug7 is a dominant with its tension raised, so it still points at F# — harder than a plain seventh does, because the altered tones sit a semitone from where they are going.
Voice by voice, C#aug7 → F#. 3 voices move by a semitone, and one note is common to both chords.
| In C#aug7 | Moves | In F# |
|---|---|---|
| C#, the root | stays where it is | C#, the fifth |
| E#, the major third | rises a semitone | F#, the root |
| A, the sharp fifth | rises a semitone | A#, the major third |
| B, the flat seventh | falls a semitone | A#, the major third |
What to play over C#aug7
Every note of C#aug7 is in C# whole tone and C# altered.
Chords near C#aug7
Change one note of C#aug7 and you have C#maj7#5 (the flat seventh becomes a major seventh), C#7 (the sharp fifth becomes a fifth), C#7b5 (the sharp fifth becomes a flat fifth), C#alt (add the flat ninth), C#aug (drop the flat seventh) or C#aug9 (add the ninth).
C#aug7 is an altered chord — a dominant seventh with its fifth or ninth moved. Altered dominant chords on every root.
On C#aug7’s sound and use this page follows Mark Levine, The Jazz Theory Book (Sher Music, 1995). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.