Chords and pentatonics

Question

I am trying to learn music theory, and I got stuck on pentatonics and I was wondering if you can help me out.

What I don't really understand: is it correct to mix pentatonic scale with its scale chords?

For example, C major scale gives us these chords:
C Major, D Minor, E Minor, F Major, G Major, A Minor, and B Diminished

And the C major pentatonic scale is: C D E G A

Is it correct to use just C major pentatonic scale for all of these chords in C scale, or we should change pentatonic scale as the chord changes? For example, if we play a C chord, we use C pentatonic; then we play an Em chord - we play Em pentatonic?

Answer 1

Let's go a bit scientific.

C maj.pent. = C D E G A

Dm pent. = D F G A C

Em pent. = E G A B D

F maj. pent. = F G A C D

G maj. pent. = G A B D E

Am pent. = A C D E G.

Common notes? Well, A fits all. D fits all. G fits all. C fits 4/6. E fits 4/6. Work out the rest for yourself! But suffice to say that the 'fits all' group all belong to C maj. pent. So that will by and large work over all the chords shown.

More important though, is targetting, and playing important notes at important places in the bar. Simple example: 1st beat of a bar is emphasised, so a key note played there will always be convincing. So in a bar of C, note C on beat 1 is a good thing. Not saying it's the only thing, but still a good thing.

So, actually, using just the C maj. pent. notes, every bar in a song in key C would have at least the first beat covered, with the exception of a bar of F. But, even then that 1st beat would sound good with an A or C note - as they also are part of the F maj. chord! There's a bit to chew on for now!

By the way, there is NO correct. Most of us can and will use any of the 12 notes available (chromatics and diatonics - which of course include those pents) and guitarists in particular will play notes 'in the cracks' too.

Answer 2

No you don't have to. Usually for pop / rock song you can keep the same pentatonic scale during chord progressions, unless there is a modulation obvious or hidden (the same chord can change function). But of course you can also change pentatonic scales during the chord progression to emphasize certain colors or avoid to be too boring.

For a major scale, there are 3 major pentatonics beginning (in C) on C, F and G. There is also 3 minor pentatonics beginning on D, E and A, which are in fact the same. (C=Am, F=Dm, G=Em)

You can play any of these scale on any diatonic chords but some will sound good, others "different".

Each one will suggest different modes / extensions

Ex. on a Dm7 chord :

Dm pentatonic will sound good but pretty basic (non chord tone : 11th); Em pentatonic will give you a real Dorian sound (i.e. on So what by Miles Davis), as it contains the 9th, 11th and 13h; Am pentatonic will sound good also on a Dm7 chord.

Other example: playing a G major pentatonic on a F chord will create a Lydian sound.

And to end: don't overuse pentatonic, try to think and play in triads (specially with approach notes = chromatic note above or below), it's far more interesting, i.e. play a Dm or F triad on a G chord...

Hope that helps.

Answer 3

You ask an either or and the answer is both. As you point out all these chords are in the same key. Therefore you can play C maj scale over all of them. You may have learnt about other modes like Dorian, Phygian, etc. While each is a distinct scale they are all related in any given Key signature. The degree chord and mode are listed below.

1 ---- Maj ---- Ionian (Major scale)

2 ---- min ---- Dorian

3 ---- min ---- Phygian

4 ---- Maj ---- Lydian

5 ---- Maj ---- Mixolydian

6 ---- min ---- Aeolian (natural minor)

7 ---- Dim ---- Locrean

You can interpret this as saying that if you are in the key of X and start playing the major scale on the 3rd degree (Mi) you are actually playing the same scale with the notes in a different order. Another way of thinking of this is that E phygian is in the key of C maj.

So what does this have to do with pentatonics? Pentatonic scales are similar to the major and minor modes with some notes removed. The major pentatonic is missing the 4th and 7th while the minor pentatonic is missing the 2nd and 6th notes. These are precisely the notes that distinguish the different modes.

Major = {1, 2, 3, 4, 5, 6, 7, 8}

Lydian = {1, 2, 3, #4, 5, 6, 7, 8}

Mixolydian = {1, 2, 3, 4, 5, 6, b7, 8}

Major Pent = {1, 2, 3, 5, 6, 8}

Dorian = {1, 2, b3, 4, 5, 6, b7, 8}

Phygian = {1, b2, b3, 4, 5, b6, b7, 8}

Aeolian = {1, 2, b3, 4, 5, b6, b7, 8}

Minor Pent = {1, b3, 4, 5, b7, 8}

The Locrean does not fit the pattern since

Locrean = {1, b2, b3, 4, b5, b6, b7, 8}

With the flat 5th the pentatonic does not really fit.

When the chords you have in a progression are all in the same key you can stay on one common scale and use your ear to move in interesting places that are complemented by the chords or you can move to a new mode or pentatonic that best fits.

Sometimes players add texture my going out of key. For example, while a D minor in the key of C would suggest D dorian you could play off Aeolian and make it work. The pentatonics represent a common thread in all major modes and three of the 4 minor modes. In that sense one can count on them to fit regardless of the key. This makes them versatile.

Answer 4

I have perhaps a bit of a different take on this. Sort of the same, but maybe a little more practical in use.

You ask if it's ok to play a pentatonic scale over the harmonized chords of the scale.

Yes...it is. And no, it isn't.

You know that a full scale has seven notes. Also, it has seven harmonized chords, based on seven modes, using Ionian (what people often think of as "the major mode") as the root.

You can apply the same thinking to pentatonic. There's only five notes in the pentatonic scale. No coincidence that there's five standard pentatonic positions, which again, would suggest it maps to five modes and chords.

Which two are missing? Again, use Ionian as the root. Pentatonic Major really is just "abbreviated Ionian". It leaves out the 4th and 7th. Those map to the Lydian and Locrian modes. Good thing; those two modes can be difficult to apply correctly, especially for the newer player.

So, let's talk scale of C Major.

Penatatonic: C D E G A C (no fourth or seventh).

That'll work fine for any of the typically harmonized chords of CMajor that map to those modes. Say for instance the composition is:

C major, D minor 7, G7, C major.

All those chords have roots in the pentatonic scale, and there are shapes for all of them (the same notes, just starting from a different root). So (naively) you could jump around the neck, starting from a given root, and play the appropriate pentatonic shape for that chord.

Now we get into why I say "yes...and no", which can lead to a much longer discussion: the notion that "all the notes are the same in every position so I can use any position over any chord in that scale" is true in one way and false in another. This is the "I'm playing the right scale why does it sound terrible" problem. For instance, while playing that G7 chord, the soloist leans on the note C. It sounds not-so-good. Why? Look at the chord; you're playing a C over a G7 chord. In terms of the chord, you are now overlaying a fourth (C is the fourth of G) onto that chord. At a basic level, sonically, it's almost certainly not what you want (try it, you'll see).

Let's analyze the chord: the tones of G7 are G B D F; neither B or F are in C pentatonic (isn't that interesting...those are the notes intentionally left out of C major pentatonic...which leads to a much longer discussion...).

So, what would be a safe choice from the scale? G and D are in G7, so those are going to be fine. A would be the 9th (2nd) of G7, and that's usually pretty safe (especially if you use a trill or something). B and F would both work, but neither of those are in the scale, so we omit them. So G, D, and to a slightly lesser degree A, are reasonable choices to land your runs on.

(By "land your runs on", I don't mean "only play those notes". I mean, as you're moving through the pentatonic pattern, be mindful what notes you stress).

Anyway, that aside, regardless of the fact that pentatonics are supposed to be "easy", you STILL need to be aware of the harmony you are playing over. And that's the thing that traps so many players. They think they can just use a single pentatonic scale over the entire composition. Again, they're right in a kind of naive way (the "math" way), but wrong in a very important way (the "sonic" way).

So what to do if there is a 4 or 7 chord (which would be chords that map to the Lydian and Locrian modes)?

Look at the notes in the chords. In C major, the 4 would be F (Lydian). We'll keep it basic and assume the #4 of Lydian is not in the chord.

F A C E

We know F isn't in C pentatonic. The rest of the notes are. So you're good. Being mindful of notes that may not be sonically straightforward (for instance, the D would be the 6th (or 13th) of F, which can create complexity you might not be looking for), you're pretty safe.

How about the 7 chord (Locrian), which would be B min7 b5?

B D F A

There's two notes in that chord that aren't in the scale. The other two are. Again, listening to those two notes, pick the one that seems to work sonically. Even though there's no pentatonic position that maps to this chord, you can still employ the pentatonic scale to create melodies and improvise over it.

There are some eclectic extensions to this conversation; modal pentatonics and such (there is inevitably a clever example of how somebody broke a given "rule"), but I think if you get what I wrote above, you'll have some fairly solid (and practical) ground to work on.

And fortunately, this applies directly to the full scale as well. The same exact thinking. Two things I never liked about how pentatonics are taught is that usually they start with the minor pentatonic (theory is based on the major scale but players are commonly taught the minor pentatonic shape first...IMHO that is a mistake, I know it held me back for a while, the whole "convert to minor" thing is a fairly advanced concept, thank you Mr. Martino), and that somehow pentatonic thinking is different or easier than regular scales. There may be less notes but the foundational thinking and concepts are identical.

Hope that helps.