Tetrachords, Scales, and Modes: Answer to a Student Question

Hey there folks, I got some more theory for you today.  Yipee!

The following is a question and answer thread from my YouTube channel, regarding my video about how to quickly visualize any major scale on your keyboard, by using something called the major tetrachord.  First, the original video, and then the Q&A.

Student: Is there something that is just as easier to use to identify minor scales?
Me: Thanks for your question! I will answer in terms of the “natural minor,” although this answer applies to the harmonic and melodic minor scales as well. First of all, the standard minor scales, as well as each of the “modes” of the major scale (dorian, mixolydian, etc), can all be broken up into tetrachords. The bad news is, the lower tetrachord of a minor scale has a different whole-step/half-step pattern than the upper tetrachord. (The cool thing about the major scale, on the other hand, as I describe in this video, is that the lower and upper tetrachords have the same pattern.) You may still find it helpful to break any scale type into two tetrachords. I hope this helps!
Student: Thank you for your reply. Do you have any videos going through each modes (Lydian, Mixolydian etc) and the easiest way to identify them using the tetrachords? Different modes have different patterns.
Me: I don’t have any videos on that yet. When I get a chance I will make a blog post (soon) on pianowithkent.com, which will give a description of my own approach to memorizing the modes. Meantime, try using C-major as your master reference. Starting there, realize that the modes of C Major all share the same pitches as C-major (the white keys of the piano). That is, Dorian mode of C Major starts on D. Phrygian starts on E. Lydian, on F. Mixolydian, on G. Aolian (aka the natural minor scale) starts on A. And finally, Locrian, which starts on B. Since these are all the modes of C major, they all use just the white keys of the piano. Use these modes as your master reference to building any given mode starting on any note. It helps to attack the problem from several angles. One angle is to break up each mode’s unique pattern into two successive tetrachords. Another is to be able to find the major scale (the parent scale) associated with the mode you want. For example, E-flat Dorian is the “Dorian mode of D-flat Major.” (By definition, they share the same pitches). Yet another angle is to become a master of every major scale and every natural minor. Then learn the modes as distinct variations of either the major or the minor. For example, Mixolydian is simply a major scale with a flatted seventh. This last approach is the one that I find easiest But in different contexts I use all these approaches. As far as the modes go, focus on Dorian, Mixolydian and Lydian. These are by far the most commonly used modes.

 

Video: Ray Charles “What I’d Say” — Practice your blues licks with this one!

 

What’s up, Blues Cats and 12-bar Chicks?

If you want to get better at your blues piano playing, who better to learn from than Ray Charles? Try playing this video while throwing in your own blues licks on top.  Also try to imitate or paraphrase some of Brother Ray’s.

Here’s some insight to help you:

(1) The key is E.  You can start joining in by using the E-minor blues scale, throughout the whole jam, right hand only.  The E-minor blues scale is E, G, A, Bb, B, D, (E). Even if that’s all you practice here — which is quite valuable — it still helps to realize the following things about the chords involved . (If you’re especially ambitious,  you can try playing these chords in your left hand, while riffing with the right.)

(2) The chords are E7, A7 (added ninth, optional), and B7.

(3) The chord progression is a classic 12-bar blues, in its most basic form, outlined here:

E7 — 4 measures (bars)

A9 (or just A7) —  2 measures (bars)

E7 — 2 measures (bars) 

B7 — 1 measure (bar)

A9 (or A7) — 1 measure (bar)

AND THE TURN-AROUND:

E7 — 1 measure (bar)

B7 — 1 measure (bar) 

Now go back to the top.

(4) Repeat the above progression over and over, as you would in any 12-bar blues.  EXCEPTION: You may notice that the B7 in the turn-around does not happen in the 12-bar introduction, where Ray is playing the left-hand bass line and nothing else.  Here, E7 is implied throughout the last two bars.

(5) In the sections where the band stops, but the singing or soloing continues (called a break, or “stop-time”), the prevailing harmony is four bars of E7, as usual. Each time this break happens, we are sitting at the top of the 12-bar cycle. Therefore, each break leads us right into the A7 at measure 5.

So here’s the video, and have fun!

More on “Fourth Chords”

Ain’t life grand? As in grand piano?

Here’s a follow up to my recent post about “Fourth Chords.” I made this second video to give more insight regarding how “fourth chord” shapes can be superimposed over various roots, to create refreshing voicings for standard chord types, such as major, minor and dominant seventh chords.  The goal here is to focus on the practical side of putting these shapes into use!

Video: Fourth Chords, Part Two

“Fourth Chords” — Very Useful (Part One)

“Fourth chords” are chords built as a “stack of fourths,” rather than as a “stack of thirds.”An example of a “stack of fourths” would be: D, G, C, and F, where D is the lowest pitch, and the rest make up a series of fourths above that.

The greatest thing about these stacks is that any given stack can be superimposed above multiple roots, to create a variety of voicings for various chord types.

Using the stack mentioned above as an example:

A “Dmin7” chord using the stack D, G, C, and F, results in a nice open-sounding voicing, with an added 11th (the “G” note is the 11th).

OR,

D, G, C and F also sounds great over a B-flat root, creating a “Bb69” sound! That is, a B-flat major chord, with an added 6th and 9th. (G is the 6th, and C is the 9th).

And so on…my video here explains this in depth. (Check back soon for Part Two, with more insights on this.)