Did you know that you can create movement with the ii chord leading to the V chord?
By using a Major 6th Diminished Scale derived off the 3rd of the ii chord, you can create additional movement with your ii chords, making your ii V I chord progressions sound better!
If you are not yet familiar with Barry Harris concepts and the different types of 6th Diminished Scales, check out the links below.
6th Diminished Scales are highly effective in creating movement with static chords and this scale can be applied to any ii V I chord progression to accomplish that.
In the key of Db major, the ii chord is Ebmin7 and the V chord is Ab7.
For your Ebmin7, think Gb6 Diminished Scale. You are deriving a Major 6 Diminished Scale off of the 3rd of your ii chord.
A Gb6 Diminished Scale has these notes: Gb, Ab, Bb, Cb, Db, D, Eb, F, Gb
This scale emphasizes the sound of a Gb6, which has the notes: Gb, Bb, Db, Eb which are the same notes as an Ebmin7.
The options for your ii chord have now expanded, by introducing the notes D and Cb.
Introducing a D and Cb over an Ebmin7 chord, implies a secondary dominant sound.
So instead of your chord progression being just Ebmin7 Ab7 Db6, you are now implying Bb7b9 Ebmin7 Ab7 Db6, which makes your overall ii V I chord progression sound smoother and better.
Below is an example of how you can apply 6th Diminished Scales to the Jazz Standard "Body and Soul".
Whenever you see a substitute 6 Chord (written above the original chord), you can play that 6 Diminished Scale.
If you are interested in learning more about Sixth Diminished Scales, I highly recommend checking out the concepts of Barry Harris:
The Barry Harris Workshop DVD - Part One
The Barry Harris Workshop DVD - Part Two
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