>Step by step
Constructing jazz scales
1 To re-examine what a scale actually is, here’s our usual jumping-off point: the C major scale. It’s a sequence of seven notes from C to B, played consecutively on the white keys of the piano keyboard. The pattern of intervals between these notes is T-T-S-T-T-T-S, where T stands for tone and S stands for semitone.
2 It’s this unique pattern that makes this scale a major scale, but this is just one of many different types of scale, each defined by its own intervallic pattern. Here’s a small selection of some other scales that use different intervallic patterns, and as such are almost guaranteed to work over specific chord types used in jazz.
3 When choosing what notes to play over a particular type of chord – such as minor 7th or dominant 7th, for example – there’s a simple rule of thumb that you can use that guarantees success almost every time. Let’s look first at a really common jazz chord, the minor 7th. Here’s
Eb, Cm7, built from the root, C, minor third
Bb. fifth G and flat seventh
4 The rule can be called the ‘Chord Tone Plus A Tone’ rule. To build the scale that works over this chord, we first need to isolate the chord tones, so in this case
Eb, Bb. that’s C, G and That’s four of the seven tones in our scale accounted for. We know these will work over a Cm7 chord, because they’re taken directly from the chord itself.
5 To fill in the gaps, we now need to count up a whole tone (two semitones) from each chord tone and include those notes in our scale. So a whole tone up from C would be D, a tone
Eb up from would give us F, and a tone up from G would give us A. The resulting
Eb Bb scale ends up being CD FGA – in other words, the C Dorian scale.
6 This approach works with any chord type in any key. Let’s try a major 7th this time – how about Emaj7? Its chord G#, D# tones are E, B and – all good so far. A F#, G# tone up from E is a tone up from A# would be and a tone up from B would C#, F# G# A# give us so that leaves us with E C# D#, B which is otherwise known as the E Lydian scale.