Static Pentatonic Scale

Question

Hello everybody I have 2 questions regarding the pentatonic scale. 1st question is.. does the pentatonic scale move according to what chord I am on in the scale? for example lets say i'm on c major and im playing the c major pentatonic scale, now lets say the song moves to D minor or the ii. Should I then move to the minor pentatonic built on D minor? My second question is regarding something in my jazz book that I hope can be cleared up for me.
It says "On major chords we can: build a pentatonic scale from the root, 5th and 9th of the chord." I dont really understand this. Does that just mean the pentatonic which is 12356 can just start on the root obviously but also start it on the 5th or 9th?? Thanks to anyone who helps. This website is amazing! thanks guys

Answer 1

Regarding your first question, you could use the pentatonic scales corresponding to the diatonic major and minor chords of a key, but you don't need to. As an example, take C major. The major and minor chords in that key are

C Dm Em F G Am

(note that I ignore the diminished chord on the seventh scale degree, because it doesn't have a related pentatonic scale).

Now note that there are only 3 pentatonic scales that cover all the chords:

1. C major / A minor pentatonic scale for C and Am
2. F major / D minor pentatonic scale for F and Dm
3. G major / E minor pentatonic scale for G and Em

Also, note that all those pentatonic scales are subsets of the complete C major scale:

C maj / A minor: C D E G A

F maj / D minor: F G A C D

G maj / E minor: G A B D E

So using the pentatonic scale corresponding to the diatonic chords just means selecting the most appropriate notes for the corresponding minor or major chord. In that sense it's a good idea to do that. But of course you never leave the basic scale, in this case C major.

Note that when more complex chords are used, such as four-part or five-part chords, different choices of pentatonic scales might be preferable, because they will emphasize the chord tensions rather than the notes of the basic triads.

Concerning your second question, building pentatonic scales on the 1, 5 and 9 of a major scale is a very common thing to do. The scale on the 1 doesn't need any further explanation, the scale on the 5 replaces the root for the major seventh, which is a good choice over a major seventh chord. E.g., over a C major seventh chord you could play the G major pentatonic scale: G A B D E

The pentatonic scale built on the 9 gives a lydian sound because it has the #11. In the key of C major you could play the D major pentatonic scale: D E F# A B, which gives you the tensions 9, #11, and 13 (6), so it would be a good choice over a C major 7 (#11) chord.