C♯ Minor 9th Chord: Notes, Voicings, and How to Play It

Fifteen scales on this site contain C♯m9 and every one of them writes it C♯, E, G♯, B and D♯. Not one respells a note. That is the opposite of the major ninth on this root, which no scale here prints as written at all. The two chords share the black keys C♯, G♯ and D♯; the minor version asks for E and B instead of two sharps that land on white keys, and in doing so it sits inside the keys guitarists already live in.

Try It: C♯m9 in the Chord Finder

The Notes of C♯m9

Three sharps and two naturals, and all three sharps are in the key signature of C♯ minor. The symbol needs no explanation and no translation, which for a five note chord on this root is unusual.

How C♯m9 Is Built

Add D♯ on top of C♯m7. D♯ is fourteen semitones above the root and E is three, so folded into one octave the ninth lands a semitone below the third: D♯ is the black key E sits against. Voice them a whole tone apart and the chord bites. Voice them a minor ninth apart, D♯ low and E high, and the same two notes sound like air.

The seventh settles which C♯ minor you are in. C♯ harmonic minor raises it to B♯, so its tonic ninth chord is C♯m(maj9), and C♯ melodic minor does the same. Only the natural seventh gives C♯m9, so a piece leaning on its raised leading note cannot rest here. That is why the list below holds natural minor and Dorian and no harmonic minor rooted on C♯.

C♯m9 on the Piano

The five keys alternate colour all the way up: C♯ black, E white, G♯ black, B white, D♯ black. Nothing in the shape doubles back, and that regularity is why it falls so easily under a hand that has not learned it.

Give C♯ to the left hand alone and play E, G♯, B and D♯ in the right. Those four are Emaj7 in root position, so plenty of pop charts write the whole thing Emaj7/C♯ and mean this exactly. Fingering 1 on E, 2 on G♯, 3 on B, 5 on D♯ keeps the hand relaxed across eleven semitones.

Three triads live inside these five notes and all three are diatonic to C♯ minor: C♯ minor at the bottom, E major in the middle, G♯ minor at the top. Any of them over a C♯ bass gives part of the chord, which is how a keyboard player gets a whole arrangement out of one harmony.

Keep D♯ high. Directly above C♯ in the left hand it fights the root; above B it becomes the brightest thing in the chord.

C♯m9 on the Guitar

The open strings help this chord and none of its neighbours. C♯maj9 and C♯add9 contain no open string at all, and C♯9 contains only the B, which its usual grip has to fret anyway. Here both E and B are chord tones, ringing on three of the six strings, and the two notes needed beyond them, G♯ and D♯, sit one fret above the open G and D.

That produces a voicing the chord books miss: x 4 1 1 0 0. Index flat across the fourth and third strings at the 1st fret, ring finger on the fifth at the 4th. Two fingers, all five notes, low to high C♯, D♯, G♯, B, E. Look where the ninth and third end up: D♯ near the bottom and E at the top, thirteen semitones apart, exactly the spacing recommended above and arrived at by accident of tuning.

Set it beside the half open C♯m7 grip on the minor seventh page, x 4 2 1 0 0. One finger slides back a fret, E on the fourth string becomes D♯, and a seventh chord becomes a ninth.

For a movable version, use x 4 2 4 4 4: middle finger on the fifth string at the 4th fret, index back to the fourth at the 2nd, ring finger flattened over the top three at the 4th. It sounds C♯, E, B, D♯, G♯, one fret from the C♯9 grip at the same position, the third being all that moves.

Higher up, 9 11 9 9 9 11 gives six strings from the 9th fret: barre, ring finger on the fifth string at the 11th, little finger on the top string at the 11th for D♯. The second string has no ninth anywhere near that position, so the top string must carry it, and losing the little finger loses the ninth.

Inversions

First inversion is not really an inversion in use. With E underneath, the four notes above it spell Emaj7 with a sixth added, and the ear follows the bass. This is the risk of the open shapes: any stray low E takes the chord away.

Third inversion is the one to keep. Over B the chord reads as a B major triad with no fifth and with C♯ and E added, so it hangs on the dominant of E major and can fall to either E or B. Fourth inversion, with D♯ underneath, sounds unfinished in a way that is occasionally exactly right at the end of a phrase.

Voicings

Four notes are plenty: C♯, E, B and D♯. The fifth goes first, as the extended chords guide explains, and G♯ is the least missed of the five because the open strings already give this chord its width on guitar.

Drop the root too and E, G♯, B and D♯ stand alone as an E major seventh, which is why bass and keyboard so often disagree about what to call it.

Spread for two hands: C♯ well below, then B, E and G♯ with D♯ on top. Seventh at the bottom of the right hand, third above it, ninth crowning.

Which Keys Contain C♯m9

• vi of E major
• ii of B major
• i of C♯ natural minor
• iv of G♯ natural minor
• iv of G♯ harmonic minor
• i of C♯ dorian

The harmonic minor entry is the surprise. G♯ harmonic minor raises its seventh to F𝄪, a double sharp played on the key called G, and no letter name would do instead. None of the five notes here touches that degree, so the minor fourth chord takes a ninth without any contact with the raised leading note.

Note what is missing from the list. A major contains C♯m7 as its third degree, but it has D natural where this chord wants D♯, so it does not hold C♯m9 at all. Raise that one degree, turning A major into A lydian, and the chord appears. One accidental decides it.

E major and B major are the practical entries. On the guitar those are home keys, and this is the sixth and the second degree of them.

Where C♯m9 Shows Up

Row three is where the harmonic minor point pays off. D♯7 is D♯, F𝄪, A♯ and C♯, and that double sharp sounds as G, so the dominant shares only C♯ and D♯ with the chord before it and three voices have to move. It is a hard, bright cadence, and putting a ninth on the iv chord widens the contrast rather than smoothing it.

Rows one and two hold identical chords doing opposite jobs, which is the useful thing about this root. C♯ minor is the relative minor of E major, so a band in E and a band in C♯ minor both arrive here, one hearing a passing colour and the other hearing home. Neither has to leave the first four frets.

Row four turns on the chord next to it. C♯ Dorian raises the sixth degree to A♯, which makes its fourth chord F♯7, a dominant seventh rather than a minor one. C♯m9 contains no sixth of its own, so it fits either mode without argument, and the F♯7 beside it is what announces Dorian. The two share C♯ and E, so the loop moves three voices and turns over without ever settling.

Related Chords

• C♯ Minor 7th Chord, the four note chord underneath, one fret away in the open position
• C♯ Minor Chord, the triad at the centre of it, with the barre positions worked out
• C♯ Major 9th Chord, the same three black keys with two very different white ones
• C♯ Minor 6th Chord, the same triad decorated from below the seventh instead of above it
• E Major 7th Chord, these five notes minus the root
• Chord Inversions and Voice Leading

Learn More

• Extended Chords and Jazz Harmony, for guide tones, rootless voicings and which tensions each chord quality will take
• Seventh Chords: The Complete Guide
• The ii, V, I Progression
• Guitar Chord Shapes: The CAGED System
• The Circle of Fifths Explained
• C♯ Natural Minor Scale, the key this chord is the tonic of