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The Altered Scale

Also known as Super Locrian and the Diminished Whole Tone scale. It is the seventh mode of the melodic minor scale, and the single most useful scale jazz musicians know for improvising over altered dominant chords. Every available tension a V7 chord can carry — ♭9, ♯9, ♯11, ♭13 — lives inside it.


01. What the Altered Scale Is

Build C melodic minor: C, D, E♭, F, G, A, B. Now start that scale on its seventh degree — B — and play through to the next B. You get B, C, D, E♭, F, G, A. That is B altered, the seventh mode of C melodic minor, and the same procedure on every melodic minor scale produces the twelve altered scales.

The shorthand is straightforward: the altered scale on a given root is the melodic minor scale a half step above that root, rearranged to start on the lower note. C altered = D♭ melodic minor; G altered = A♭ melodic minor; F altered = G♭ melodic minor. Once that pattern clicks, you can derive all twelve altered scales from a single shape.

It earned the name “Super Locrian” because it looks like the Locrian mode (1, ♭2, ♭3, 4, ♭5, ♭6, ♭7) with the 4th degree lowered to ♭4. One more flat below Locrian — “super” in the sense of more so — and you arrive here.


02. Two Formulas, One Scale

The altered scale is unusual in that it has two standard formulas, each useful in a different situation. The first matches the modal spelling — one note per letter name. The second matches the chord-tone alterations of a dominant 7 chord.

Modal spelling (Super Locrian)

1 — ♭2 — ♭3 — ♭4 — ♭5 — ♭6 — ♭7

1
C
♭2
D♭
♭3
E♭
♭4
F♭
♭5
G♭
♭6
A♭
♭7
B♭

This spelling makes the relationship to other modes obvious. Compare against Locrian (1, ♭2, ♭3, 4, ♭5, ♭6, ♭7): everything matches except the 4th, which the altered scale lowers to ♭4. The strict alphabetical order (one note per letter) also makes notation cleaner — but for some keys it produces double flats, which is why the second formula often takes over in practice.

Jazz spelling (altered dominant)

1 — ♭9 — ♯9 — 3 — ♯11 — ♭13 — ♭7

1
C
♭9
D♭
♯9
D♯
3
E
♯11
F♯
♭13
A♭
♭7
B♭

Same notes (F♭ = E, G♭ = F♯, etc.), different labels. This is the spelling jazz pianists actually think in, because it names every note as a chord tone or available tension over a V7 chord. The chord tones of C7 — 1, 3, ♭7 — sit unchanged at C, E, B♭. The remaining four notes are exactly the four altered tensions ♭9, ♯9, ♯11, ♭13.

Why two spellings? The modal spelling keeps the scale alphabetically ordered (C–D–E–F–G–A–B with appropriate flats). The jazz spelling keeps every note inside the standard chord-tension vocabulary. Most jazz fake books use the jazz spelling; most theory textbooks use the modal one. They describe the same seven pitches.

03. Built on the Seventh Degree of Melodic Minor

Every mode of melodic minor has a use: the second mode (Dorian ♭2) handles minor-7 chords with a flat 9, the fourth (Lydian dominant) handles dominant chords with a ♯11, and so on. The seventh mode is the most useful of all, because it covers every alteration of a dominant chord at once.

The shortcut is worth memorizing. To find the altered scale on any root, build the melodic minor scale a half step higher. The notes are identical; only the starting point changes.

Altered ScaleParent (Melodic Minor)
C alteredD♭ melodic minor
G alteredA♭ melodic minor
D alteredE♭ melodic minor
F alteredG♭ melodic minor
B alteredC melodic minor

If you already know your melodic minor scales, you already know your altered scales. The note content is the same set; the harmonic role and starting note are what change.


04. Hear It in Every Key

Click a root to highlight that altered scale on the keyboard, then press play to hear it ascending and descending. Notice how strange it sounds standing on its own — and how much its dissonance starts to make sense once you imagine it sitting on top of a dominant 7 chord.

Widget · Altered Scale in 12 Keys

C
D
E
F
G
A
B
C
D
E
F
G
A
B

C altered: C – D♭ – E♭ – F♭ – G♭ – A♭ – B♭

Parent scale: D♭ Melodic Minor (the altered scale is the seventh mode).


05. The Altered Scale in All Twelve Keys

Every altered scale uses the semitone pattern H – W – H – W – W – W – W (1, 2, 1, 2, 2, 2, 2). The table below lists all twelve, the readable note spelling, and the parent melodic minor scale they come from.

RootNotesParent
CC – D♭ – E♭ – F♭ – G♭ – A♭ – B♭D♭ Melodic Minor
C♯ / D♭C♯ – D – E – F – G – A – BD Melodic Minor
DD – E♭ – F – G♭ – A♭ – B♭ – CE♭ Melodic Minor
D♯ / E♭D♯ – E – F♯ – G – A – B – C♯E Melodic Minor
EE – F – G – A♭ – B♭ – C – DF Melodic Minor
FF – G♭ – A♭ – A – B – D♭ – E♭G♭ Melodic Minor
F♯ / G♭F♯ – G – A – B♭ – C – D – EG Melodic Minor
GG – A♭ – B♭ – C♭ – D♭ – E♭ – FA♭ Melodic Minor
G♯ / A♭G♯ – A – B – C – D – E – F♯A Melodic Minor
AA – B♭ – C – D♭ – E♭ – F – GB♭ Melodic Minor
A♯ / B♭A♯ – B – C♯ – D – E – F♯ – G♯B Melodic Minor
BB – C – D – E♭ – F – G – AC Melodic Minor

Most keys spell cleanly (one note per letter). A handful — F, and the four sharp/flat enharmonics — are easier to read with mixed accidentals; the strict modal spelling for those keys requires double flats. The note content is identical either way.


06. How to Use It — V7alt → I

The altered scale shines in one specific spot: the dominant chord that resolves down a fifth to its tonic. Play the chord altered, play the scale altered, then resolve. The scale gives you every tension you might want, and the resolution releases all of it.

The classic move: G7alt → CMaj7

Over the G7, play G altered: G, A♭, A♯, B, C♯, E♭, F. The chord under it is some voicing of G7♭9♯9♭13 (a “G7alt” voicing). On the bar of CMaj7, drop into the C major or C Lydian scale. Every dissonant note you played over the G7 has a target a half step away inside CMaj7 — that is the resolution.

Why it works mechanically

The altered scale on the V chord shares no notes with the I major chord except the leading tone (B in the case of G→C). Every other note is dissonant against the tonic. That maximum tension is exactly what you want at the moment before resolution; the ear hears the V7alt as wanting to move, and any reasonable line resolves naturally.

Voicing tip for piano

Avoid playing the natural 5 of the dominant chord while the altered scale is in the air. The natural 5 contradicts the ♭5 (♯11) and ♯5 (♭13) that define the alterations. On G7alt you would voice the chord with the 3 (B), ♭7 (F), and a pair of altered tensions — for example ♭9 (A♭) and ♯9 (B♭) — but skip the natural D.


07. The Chord Voicings It Pairs With

The altered scale fits any dominant chord with one or more alterations. Each of the chords below contains the tonic, major third, and ♭7 of a V chord, plus at least one tension that lives inside the altered scale. Use the scale freely over any of them.

7♭9 (e.g. G7♭9)
G – B – D – F – A♭
The single most common altered dominant. The ♭9 (A♭) is in the altered scale at the ♭2 / ♭9 position. The natural 5 (D) is technically still here — modern voicings often replace it with ♯11 or ♭13 to point harder at the altered scale.
7♯9 (the “Hendrix” chord)
G – B – D – F – B♭ (♯9 = enharmonic ♭3)
The blues-rock favorite. The ♯9 against the natural 3 produces the classic bluesy crunch. The altered scale carries both the ♯9 and the ♭9 — modern jazz uses both interchangeably over a 7♯9 voicing.
7♯11 (Lydian dominant alternative)
G – B – D – F – C♯
Strictly speaking, 7♯11 with a natural 9 calls for the Lydian dominant scale (the 4th mode of melodic minor), not the altered scale. But the moment any other alteration is added (♭9 or ♭13), the altered scale takes over.
7♭13 (the “cinematic” dominant)
G – B – F – E♭ (♭13 = enharmonic ♯5)
Often voiced without the 5th to clear the way for the ♭13. The dark, suspended quality of this chord is almost entirely due to the ♭13, which is the ♭6 of the altered scale.
7alt — the umbrella label
G – B – F – plus any combination of ♭9, ♯9, ♯11, ♭13
When a chart says “G7alt,” the composer is leaving the alterations to the player’s taste. The altered scale is the safe, complete choice — every tension you might add belongs to it.

08. Where You’ll Hear It

The altered scale is the post-bop sound. Bebop players reached for it on dominant chords, but it became central to the modal-and-after generation that followed.

John Coltrane

Coltrane’s playing on Giant Steps and the modal records that followed leans on melodic-minor modes throughout, with the altered scale appearing routinely on the V chord of every II–V–I. Listen to his dominant resolutions on tracks like “Countdown” or his solo on “Inch Worm” from the 1962 sessions — the altered scale’s fingerprint (♯9 leaning into 3) is everywhere.

Wayne Shorter

Shorter writes harmony that demands the altered scale by structure. His Blue Note records (Speak No Evil, Adam’s Apple, Juju) routinely place altered dominants in surprising places, and his solos respond with altered-scale lines that sound simultaneously logical and inevitable. The composition “Footprints” — a minor blues — uses altered dominants on the V chords as a structural device.

Herbie Hancock

Hancock’s comping behind Miles Davis and on his own records (Maiden Voyage, Speak Like a Child) treats the altered scale as the default vocabulary for any tense dominant. His later acoustic playing — the early-70s trio recordings, the post-bop revival of the 80s — turns altered-scale runs into a kind of signature, especially on dominant chords held across multiple bars.


09. How to Practice It

The altered scale is awkward in isolation — its tonal center is unstable, and ascending it from the root sounds like a misprint. Practicing it as a stand-alone scale is necessary but never sufficient. The real skill is connecting it to the chord under it and resolving it correctly.

1. Learn it as melodic minor a half step up

If your melodic minor scales are solid, the altered scale is free. Practice C melodic minor; play it again starting on B (the seventh degree); that is B altered. Repeat on every melodic minor scale you know.

2. Practice over II–V–I, not over V alone

Loop a Dm7 → G7alt → CMaj7 progression on a backing track. Play through the changes using D Dorian on the Dm7, G altered on the G7, and either C major or C Lydian on the CMaj7. The point is the resolution; the altered scale earns its keep at the bar line.

3. Target chord tones on the resolution

Every note in the altered scale has a target a half step away inside the I chord. Practice landing on the 3rd or 7th of the I chord on beat 1, and pick the altered-scale note a half step above or below as your last note on the V. The melodic motion will sound resolved every time.


10. Continue Learning

The altered scale sits inside a small family of jazz-essential scales — all of them modes of melodic minor, all of them tools for specific harmonic situations. Once you have the altered scale under your fingers, the natural next steps are the rest of the melodic minor modes, the chord vocabularies that pair with them, and the practice routines that internalize them.


Frequently Asked Questions

What is the altered scale?

A seven-note scale built from the seventh degree of melodic minor. C altered uses the same notes as D♭ melodic minor: C, D♭, E♭, F♭, G♭, A♭, B♭. It contains every available alteration of a dominant 7 chord (♭9, ♯9, ♯11, ♭13), which is why jazz musicians reach for it over altered dominants.

Why is it also called Super Locrian?

It looks like Locrian (1, ♭2, ♭3, 4, ♭5, ♭6, ♭7) with the 4th lowered to ♭4 — one more flat below Locrian, hence "super." Jazz musicians more often say "altered" or "altered dominant"; classical theorists more often say "Super Locrian." The two names describe the same notes.

Why does the altered scale have two formulas?

The modal spelling (1, ♭2, ♭3, ♭4, ♭5, ♭6, ♭7) keeps the scale alphabetically ordered. The jazz spelling (1, ♭9, ♯9, 3, ♯11, ♭13, ♭7) names every note as a chord-tone alteration over a V7 chord. They describe the same seven pitches; the jazz spelling is more useful when you are improvising over V7alt.

When do I use the altered scale?

Over an altered dominant chord that is moving down a fifth to its tonic — the V7alt → I cadence. The classic example is G7alt → CMaj7: play G altered over the G7, then resolve into C. The altered scale carries every available tension, so it produces maximum tension into the resolution.

What chord does the altered scale fit?

Any dominant 7 chord with one or more alterations: 7♯9, 7♭9, 7♯11, 7♭5, 7♭13, and the catch-all 7alt. The scale contains the chord tones (1, 3, ♭7) plus all four available tensions (♭9, ♯9, ♯11, ♭13). It does not contain a natural 5, 9, 11, or 13 — which is exactly why "alt" is the right label.

Is the "Diminished Whole Tone" scale the same scale?

Yes — it is the same scale under a different name. The lower half of the altered scale (1, ♭2, ♭3, 3) opens with the same intervals as a diminished scale. The upper half (♯11, ♭13, ♭7, 1) is a whole-tone fragment. Combining the two halves on a single root produces the altered scale, which is why the descriptive name "Diminished Whole Tone" sometimes appears in older theory texts.

Related Tools

Circle of FifthsVisualize key relationships, relative minors, and key signatures.Chord FinderLook up any chord — see the notes, hear it, and play along.

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