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Dominant 7th #11

7#11

Altered Chords
5 notesIntervals:0 - 4 - 7 - 10 - 18

Dom7 with augmented 11th (Lydian dominant)

About Dominant 7th #11

A dominant seventh sharp eleven chord is a dominant with a raised fourth added above the fifth — in C that is C, E, G, B♭ and F♯, written C7♯11. It is the Lydian dominant sound: a chord that pulls like a dominant and floats like a Lydian major chord at the same time.

Notes and formula

The formula is 1 – 3 – 5 – ♭7 – ♯11, or 0 – 4 – 7 – 10 – 18 in semitones. The perfect fifth stays, which is the difference between this chord and a flat five.

With both G and F♯ present the chord holds a semitone inside it, but they sit an octave apart in practice, so the interval reads as colour rather than clash.

Where it comes from

The fourth mode of melodic minor, usually called Lydian dominant. Build a chord on the fourth degree of G melodic minor and this is what appears — a scale with a major third, a flattened seventh and a raised fourth.

It also arises functionally on the flattened seventh degree of a major key, where the raised fourth is simply the tonic of the key still sounding above a borrowed chord.

How to play it

On guitar the practical form is x–3–2–3–x–2, sounding C–E–B♭–F♯: root, third, seventh and raised eleventh, with the fifth left to the bass. It is the same grip as a plain dominant with the top string moved.

On piano the clearest voicing puts C low, then E and B♭, and F♯ at the top. Putting F♯ next to G in the middle of the chord is the one arrangement to avoid.

Where you hear it

In fusion and modern big-band writing it is a default dominant, not a special colour. In film scoring it appears wherever a dominant needs to sound wide rather than urgent.

It is also common in Brazilian music, where dominant chords routinely carry a raised eleventh without the arrangement drawing attention to it.

Sharp eleven or flat five

C7♭5 replaces the fifth and is symmetrical — the same chord a tritone away. C7♯11 keeps the fifth, has five notes, and is not symmetrical at all.

The audible difference is the anchor. With G present the chord has a clear root; without it the root is a matter of context.

Scales that contain it

Lydian dominant fits exactly and is the standard answer. The whole-tone scale fits everything except the perfect fifth, so it works only if the voicing drops it.

Mixolydian does not fit: its natural fourth is the note this chord raises, and the two cannot sound together.

Frequently asked questions

What notes are in a C7♯11 chord?

C, E, G, B♭ and F♯. On guitar, x–3–2–3–x–4, which leaves the fifth to the bass.

What is the difference between 7♯11 and 7♭5?

Whether the perfect fifth is present. Sharp eleven keeps it and adds the raised fourth above; flat five replaces it. The chords sound different because one is anchored and the other is symmetrical.

Which scale goes with it?

Lydian dominant — the fourth mode of melodic minor. Mixolydian does not work, because its natural fourth contradicts the chord's defining note.