First off, the pentatonic scale is easy to learn and to remember. Here’s an infinite string scale pattern:
|---|-X-|---|-X-|---|---|---| |---|-X-|---|-R-|---|---|---| |---|-X-|---|-X-|---|---|---| |---|-R-|---|---|-X-|---|---| |---|-X-|---|---|-X-|---|---| |---|---|-X-|---|-X-|---|---| |---|---|-X-|---|-R-|---|---| |---|---|-X-|---|-X-|---|---| |---|---|-R-|---|---|-X-|---| |---|---|-X-|---|---|-X-|---|
Pentatonic can be used in three ways. The first is used with the root note as marked in the diagram above. This is the traditional “Blues Scale”. This mode works well against major and dominant chords.
The second way to use this pentatonic scale is to think of it as a minor 11th arpeggio (basically a minor chord with an added 4th).
The third way to use this scale is to think of it as a subset of the major scale based on the second note of the pentatonic scale. Here’s an example, if the root of the pentatonic is A, then the notes in the scale are A,C,D,E & G. All of these are notes in the scale of C major. Furthermore, the contentious 4th note of the C major scale is left out. The 4th note of the scale is often an “avoid” note in many applications. When using the scale this way, the easiest way to use it is to locate the pentatonic scale with the root the same as the major scale, and then drop down three frets.
Here’s how you can fake an entire jazz career using pentatonics: The main reason why players learn scales in different modes, is to understand where the avoid notes are. Since the pentatonic scale is stripped down to start with, this tends to be less of an issue and you can usually fake your way through most things by substituting one of several pentatonic scales.
Here’s the key: All of the major scale modes in any key can be easily translated back to an Ionic mode scale in some key. You can substitute a pentatonic scale used in the third way listed above for that Ionic mode scale. It’s easier than it sounds. For instance, D Dorian is simply C Ionian, so you can substitute an A Blues scale for it. G Mixolydian is also the same as C Ionian, so you can use the A Blues for it also. F Lydian is also the same as C Ionian.
Generally, if the harmony of a song is using a major chord, you can improvise over it using an Ionian or Lydian mode pentatonic scale equivalent. If the chord is minor, use a Dorian mode equivalent pentatonic scale. If the chord is dominant, use a Lydian equivalent.
The basic 12 bar blues in a major key will have three chords in it. A chord based on the root of the key, one on the 4th and one on the 5th. It is possible that all the chords will be played as dominant chords, sometimes only the one based on the 5th is dominant. Let’s assume that the song is a blues in A. The chords are: A maj, D maj and E dom.
For the A maj chord:
For the D maj chord:
For the E dom chord: