Using the Mixolydian Scale Effectively in a Blues ProgressionPodcast #10 - Additional notes

© Copyright Darren Dutson Bromley 2012

Playing the Blues.

There is nothing better than playing the blues and a good understanding of its structure, licks and scale possibilities are essential. It's also a really good place to start when developing skills using Mixolydian scales.

Generally when we think of blues we assume a twelve bar structure. What goes into those twelve bars varies, it can be a simple three chord progression to a much more complicated sequence using many chords. This week we'll focus on a relatively straight forward progression using chords I, IV and V.

When harmonised the Bb major scale looks like this:

Bb C D Eb F G A

Bb Cm Dm Eb F Gm Adim

Chord I is Bb, chord IV is Eb and chord V is F.

These are usually played as dominant 7th chords. The reason for this is a complicated one and is to do with combining these chords with the notes of a minor pentatonic scale which is a scale often played over these chords.

Bb Minor Pentatonic: Bb Db Eb F and Ab.

In traditional harmony it is only chord V which can be a dominant 7th.

In the key of Bb chord V is F7 which contains the notes F A C and Eb, all these notes occur within the Bb scale. Chord I and chord IV if extended to include the 7th would both be major 7th chords.

Bbma7 contains the notes Bb D F and AEbma7 contains the notes Eb G Bb and D.

The difference between a major 7th chord and a dominant 7th is, in a dominant 7th the actual 7th is a tone below the root while in a major 7th it is only a semitone.

Eb to F is a tone, hence F7 being a dominant 7th (F A C Eb). A to Bb is a semitone hence Bbma7 (Bb D F A)

To turn Bbma7 to Bb7 we need to flatten the 7th so we arrive at the notes Bb, D, F and Ab. To turn Ebma7 to Eb7 we do the same and get Eb G Bb and Db.

So where do these notes come from? They don't come from the major scale but actually from the minor pentatonic scale which is associated with it.

Bb minor pentatonic scale contains the notes Bb Db Eb F and Ab. This scale contains all the 7ths for each of the chords and the chords borrow their 7ths from this scale.

Bb7 = Bb D F AbEb7 = Eb G Bb DbF7 = F A C Eb

Here is a blues progression in Bb using the above chords.

Often the scale played over this progression is Bb minor pentatonic scale or Bb blues scale. The difference between these two scales is just one note, the blues scale also includes a flattened 5th, this turns the scale from being pentatonic (5 note scale) into a hexatonic (6 note scale).

Using Mixolydian scales.

As the chords used in this progression are all dominant 7th chords we could use a different set of scales over it.

Thinking about each chord individually Bb7 could be considered to be the root, 3rd, 5th and flattened 7th notes of a Bb major scale.

Bb major Scale

Bb C D Eb F G A

Bb7 chord Bb D F Ab(b7)

As the 7th is altered in the chord it could be altered in the scale so it matches. This is Bb mixolydian. Bb C D Eb F G Ab Bb, basically a Bb major scale with a flattened 7th note.

Applying this concept to the other chords we get:

Eb major Scale

Eb F G Ab Bb C D

Eb7 chord Eb G Bb Db(b7)

Eb Mixolydian would be Eb F G Ab Bb C Db Eb

F major Scale

F G A Bb C D E

F7 chord F A C Eb(b7)

F Mixolydian would be F G A Bb C D Eb F

When using these scales over a blues sequence, each scale must correspond to the chord been played. When Bb7 is been played you can play Bb mixolydian, Eb7 play Eb mixolydian and F7 play F mixolydian. This takes practice but it is well worth the effort. The most important thing is to make sure you know where you are in the sequence at all times.

Here is a solo based around the Bb blues changes using mixolydian scales.

See you next time