Major 9th #11
maj9#11
0 - 4 - 7 - 11 - 14 - 18Major9 + augmented 11th (Lydian)
About Major 9th #11
A major ninth sharp eleven chord is a major ninth with the raised fourth added — in C that is C, E, G, B, D and F♯, written Cmaj9♯11. It is the Lydian mode written out as a single chord: six of the mode's seven notes, stacked in thirds, with nothing left to guess.
Notes and formula
The formula is 1 – 3 – 5 – 7 – 9 – ♯11, or 0 – 4 – 7 – 11 – 14 – 18 in semitones. Only the sixth degree of the mode is missing.
Because the eleventh is raised, nothing in the chord collides. A natural eleventh would sit a semitone from the third; raised, it is a whole tone away and reads as the brightest note in the stack.
How to play it
On guitar all six notes are impractical. The working shape is x–3–4–4–3–x with the ninth added on top where the hand allows, or more simply the maj7♯11 grip with a D somewhere above.
On piano the chord is one of the few that benefits from being played nearly in full: C low, then E–B–D–F♯. The fifth is the note to drop if the voicing gets crowded.
What it is for
Stating a mode in one gesture. A single strike of this chord tells a listener the passage is Lydian, where a plain major seventh would leave the question open until the melody answered it.
That makes it a favourite of film composers and arrangers writing pads: the harmony does the work that would otherwise need eight bars of melody.
Where you hear it
Film scoring for openness and scale. Fusion, where non-tonic major chords are routinely given the raised eleventh. Japanese city pop and Brazilian writing, both of which treat the sound as ordinary rather than special.
It is rare in songwriting because it constrains a melody: with the raised fourth already sounding, a singer landing on the natural fourth will be a semitone out.
Against its smaller relatives
Cmaj7♯11 is the same idea without the ninth — five notes, easier to voice, the same mode implied. Cadd♯11 drops the seventh as well and states Lydian in four notes.
This chord is the fullest of the three and the least flexible. It works where there is room and sounds crowded where there is not.
Scales that contain it
Lydian, and nothing else without alteration. Ionian contains the natural fourth the chord raises, and every minor mode contradicts the third.
For a soloist that is a licence: over this chord the raised fourth is a landing note rather than a passing one, which is the whole character of Lydian playing.
Frequently asked questions
What notes are in a Cmaj9♯11 chord?
C, E, G, B, D and F♯. On guitar the practical form drops the fifth or the ninth depending on the shape.
How is it different from maj7♯11?
The ninth. Both state Lydian; this chord adds one more note of the mode and needs more room in the arrangement.
Can I use it as a tonic?
Yes, if the piece is in Lydian. In an ordinary major key it works better on the fourth degree, where the raised eleventh is diatonic.