Other Scales

Every scale in this chapter is a set of changes to the major scale: a degree lowered (b), raised (#), removed, or added. Each number in a formula is an interval above the root, so a b turns that interval minor and a # turns it augmented. If you can read 1 2 3 4 5 6 7, you can read all of them.

Three kinds of change appear again and again. Fewer notes (pentatonic) makes a scale safer and more open. Lowered or raised notes (the minors, the modes of the minors) change its mood. Extra notes (blues, bebop) add colour or rhythm. Listen to the plain ruler, then its darker twin, then the three kinds of change in a row.

The major pentatonic is the major scale with two notes removed, degrees 4 and 7, and it is the most widely used scale on Earth.

Why those two? In the major scale, 4 and 7 are the tendency tones: 7 pulls hard up to 1 and 4 pulls down to 3, and together they form the tense tritone (F and B in C major). Remove them and every remaining note is stable or gently unstable. Nothing clashes, nothing demands to resolve.

That is why the major pentatonic sounds so open and singable. It is the sound of folk melodies from China to Appalachia to West Africa, and of countless pop hooks. It works over any chord progression in its major key, which makes it the perfect first scale for improvising: it is almost impossible to play a wrong note.

The minor pentatonic is the natural minor scale with degrees 2 and b6 removed, and it is the home scale of rock, blues, and R&B.

Compare it with the natural minor 1 2 b3 4 5 b6 b7. The 2 and the b6 are gone: the two notes that sit only a minor second away from a chord tone (b6 leans down onto 5, and 2 in a minor scale is the one that most often clashes over minor chords). What is left is five notes that all sound good over a minor chord.

Now look again at the notes: A C D E G. Those are exactly the notes of C major pentatonic (C D E G A) started from A. The major and minor pentatonic are relative scales, the same way C major and A minor are: one collection of five notes, two different homes.

The blues scale is the minor pentatonic plus one added note, the b5 or "blue note", and that single note is what turns a rock scale into a blues scale.

The b5 is a diminished fifth above the root, squeezed between the perfect fourth and the perfect fifth, so it is rarely a note you land on. It is a note you pass through, 4 → b5 → 5, imitating the way a singer or guitarist bends a note upward. That chromatic slide is the sound of blues.

Blues also lives on a deliberate clash. Over an A7 chord (1 3 5 b7: A C# E G) the blues scale plays C, the b3, against the chord's C#. In most styles that is a mistake; in blues it is the point. Players bend the b3 up toward the 3 and the b5 up toward the 5, hovering between major and minor.

Harmonic minor is the natural minor scale with the 7th degree raised back to a leading tone, and it exists to give minor keys a real dominant chord.

In natural minor (1 2 b3 4 5 b6 b7) the chord on degree 5 is minor: in A minor it is Em (E G B). A minor v chord pulls only weakly toward the tonic. Raise the b7 (G) to 7 (G#), a major seventh above A, and the chord on 5 becomes E major. With its 7th it is E7 (1 3 5 b7: E G# B D), a true V7 with a leading tone G# just one semitone below A.

The price of that leading tone is the gap it opens. From b6 up to 7 (F to G#) is an augmented 2nd: the major second F to G, stretched because the G has become G#. It sounds as wide as a minor 3rd yet joins two adjacent degrees, and it gives harmonic minor its exotic, "classical" or "Middle Eastern" colour.

Phrygian dominant is the harmonic minor scale played from its 5th degree, and it is *the* scale for a V7 chord that is about to resolve to a minor chord.

Just as the major scale has seven modes, so does harmonic minor. Its fifth mode is by far the most used. Start A harmonic minor on E and you get E F G# A B C D: it contains every note of E7 (E G# B D) plus the b2 (F) and b6 (C) that belong to the key of A minor. The name says it all: it looks like Phrygian (1 b2 b3 4 5 b6 b7) but with a major 3rd, so it fits a dominant chord.

The b2, a minor second above the root, gives the scale its Spanish, flamenco, and Middle Eastern flavour, and the b6 → 5 and b2 → 1 pulls, each only a minor second, make the eventual resolution to Am feel inevitable. Compare it with E Mixolydian (1 2 3 4 5 6 b7), the everyday scale over E7 in a major key: same chord tones, but Mixolydian's 2 and 6 (F# and C#) belong to A major, not A minor.

Melodic minor raises both the 6th and the 7th degree of natural minor. It keeps harmonic minor's leading tone but smooths out the augmented 2nd.

Harmonic minor solved the dominant problem but left that F to G# leap. Raise the b6 to 6 as well (a major sixth above A: F#) and the scale climbs E F# G# A in even steps. The result is a major scale with only one change: a b3. A B C D E F# G# is A major with C instead of C#.

In classical practice melodic minor is used ascending (with 6 and 7) and switches back to natural minor descending (with b6 and b7), because a falling line does not need a leading tone. Jazz musicians ignore that and play 1 2 b3 4 5 6 7 in both directions, the so-called *jazz minor*, because they value it as a source of modes: two of the most important jazz scales are modes of melodic minor, and we meet them next.

The 4th and 7th modes of melodic minor, Lydian dominant and the altered scale, are the two dominant-chord colours that jazz players reach for most after Mixolydian.

Start A melodic minor on its 4th degree, D, and you get D E F# G# A B C. Against D that is Mixolydian (1 2 3 4 5 6 b7) with a #4, an augmented fourth above the root. It contains D7 (D F# A C) and adds the bright, floating #11 (G#). It is the scale for a dominant chord that is not going to resolve down a fifth: a IV7 in a blues, a bVII7, or any 7#11 chord.

Now start A melodic minor on its 7th degree, G#: G# A B C D E F#. Against G# this is 1 b2 b3 3 b5 b6 b7: the root, 3rd (C, spelled B# in the chord) and b7, and then every alteration a dominant chord can take: b9, #9, #11, b13. There is no natural 5 and no natural 9. It is the scale for G#7alt, the maximum-tension dominant that resolves to C#m. Transposed to the key of C, it is the scale for G7alt (from Ab melodic minor) resolving to C.

The whole-tone scale has six notes, each one a major second (a whole tone) above the last. Because every step is identical, it has no leading tone and no home.

A major scale has two minor-second steps (3 → 4 and 7 → 1) that tell your ear where the tonic is. Take them away, so that every step is a major second, and the scale becomes perfectly symmetrical: start on any note and it sounds the same. There is no perfect 5th above any note, no leading tone, no resolution, just a dreamy, weightless shimmer, the sound of Debussy and of a thousand film "dream sequence" cues.

Because of the symmetry there are only two whole-tone scales in existence: the one containing C (C D E F# G# Bb) and the one containing Db (Db Eb F G A B). Every other starting note gives you one of those two collections.

Its cousin, the augmented scale, alternates a wide step and a narrow one: an augmented second (1 to #2, the sound of a minor third) followed by a minor second (#2 to 3), then the same pair again from 3 and from b6. It is two augmented triads a minor second apart (C E G# and B D# G), and it fits C+ and Cmaj7#5. Rarer than whole tone, but the same idea: symmetry instead of a home.

The diminished scales are eight-note symmetrical scales that alternate a minor second and a major second (a half step and a whole step, which is where their names come from). One version belongs over a 7b9 chord, the other over a dim7 chord.

Starting with the minor second gives the half-whole scale. Look at what it contains: the whole C7 chord (1 3 5 b7: C E G Bb) plus the tensions b9, #9, #11 and 13 (Db, Eb, F#, A). Unlike the altered scale it keeps the natural 5 and 13, so it is the scale for C7b9 and C7#9: a dominant with a bite but still a solid core. Plain Mixolydian remains the default over an unaltered C7; the half-whole scale is what you switch to when the chord symbol says b9 or #9.

Starting with the major second gives the whole-half scale. It contains the entire Cdim7 chord (1 b3 b5 bb7: C Eb Gb A) with a major second above each chord tone, so running the scale connects the chord tones smoothly. Notice that whole-half on C is the same collection as half-whole on D. The two scales are modes of each other.

Because the pattern repeats every minor third, there are only three diminished collections in total (on C, C# and D); every other root gives one of those three. That is also why one dim7 chord can resolve in four different directions.

A bebop scale is a seven-note scale with one chromatic passing tone added, eight notes in total, placed so that the chord tones land on the beat when you play the scale in eighth notes.

Here is the problem it solves. Mixolydian has seven notes. Play it down from the root in eighth notes, C Bb A G F E D C, and the chord tones C Bb G E fall on beats 1, 2, 3 and 4... but only because you started on the root; the next octave falls off the grid. Add one note, the major 7 between b7 and 1, and the scale has eight notes: C B Bb A G F E D. Now C lands on 1, Bb on 2, G on 3, E on 4, and the pattern repeats every bar forever. The passing tones (B, A, F, D) always fall on the off-beats.

The same trick over a major chord: add a #5 between 5 and 6. Coming down C B A G# G F E D, the Cmaj7 tones C, A (the 13), G, E sit on the beats. It is the sound of Charlie Parker and Bud Powell: smooth chromatic lines that always seem to know where the chord is.

Zoom out: every scale in this chapter is chosen by asking one question. What chord is sounding, and where is it going? Here is the map. Every formula plays from C so you can compare them side by side.

Notice how many rows are dominant chords. A single G7 in C major can be coloured six different ways just by choosing a scale, and every choice is a formula you can now read at a glance. Hear four of them over the same G7 → C.

One more idea hides in this chapter. Harmonic minor and melodic minor are parallel scales of natural minor: same root, different notes. The next chapter takes that further. It puts C major next to C minor and lets the major key borrow chords from its parallel minor: bVII, bVI, iv. That is modal interchange.