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© 2001 James Walker This month's lesson is geared towards educators and beginning improvisers. The Junior High School or High School jazz band is usually a student's first introduction to jazz improvisation, and is the first time he or she has been asked to perform music which has not already been written out. What follows are some "shorthand" methods for understanding what pitches are most suitable for improvising over a given chord. While it is not intended to substitute for a thorough understanding of jazz theory or functional harmony, it will allow a beginner to start improvising without having to deal with hours and hours of theoretical studies.
Starting Point: The Major Scale Most instrumental music students at the high school level know their major scales - perhaps not in all twelve keys, but at least they know how the scale is constructed. Therefore, we will use the major scale as our starting point. From that scale, we can construct a major seventh chord, using the first, third, fifth, and seventh scale degrees:
Using Chromatic Alteration to Spell New Modes "Chromatic alteration" is just a fancy term for lowering or raising a pitch by half step. Using the major scale, one can create the mixolydian mode, by lowering the seventh scale degree by one half step; that is accomplished here by changing the B-natural to a B-flat.
Just as we derived the major seventh chord from the major scale, so can the dominant seventh chord be derived from the mixolydian mode, by using the first, third, fifth, and seventh degrees:
The same process holds true for creating the dorian mode, for use over a minor seventh chord. To construct the mode, lower the third and seventh degrees of the major scale by a half-step each:
...and as before, the minor seventh chord can be derived from the dorian mode, again using the first, third, fifth, and seventh notes of the scale:
NOTE TO BEGINNING IMPROVISERS: Don't get too hung up on the terms "dorian mode" and "mixolydian mode" - they deal with another approach to figuring out what notes you are recommended for use over a certain chord. Basically, modes are created by taking the major scale, but starting and ending on a note other than the root of that major scale. Look in the example above: there are two flats in C dorian. If you know your major scales, you know that B-flat is the major key which uses two flats; C dorian is simply the same pitches as the B-flat major scale, but starting and ending on C. Again, don't worry about this - it is a different approach from the one being presented in this month's lesson. Both are valid, both are useful, but don't fret too much about memorizing the names "dorian," "mixolydian," etc. Using Chromatic Alteration to Spell Chords The same way we took the major scale and lowered certain notes to spell out new modes, it is possible to take the major seventh chord and spell out dominant and minor seventh chords by lowering certain pitches by half-step.
Review To sum up, if you remember a couple of quick shorthand rules, it is fairly simple to spell out your dominant and minor seventh chords, or remember your mixolydian and dorian modes, if you know your major scales to start with.
While there is certainly much more to jazz harmony than what is presented here, the information in this month's lesson will help a beginning student to "get his feet wet" with improvisation, by providing a minimum amount of theoretical knowledge to figure out what pitches he can use.
(This page and all the materials within copyright ©2001 James Walker, All Rights Reserved. No portion of this page may be duplicated or distributed without the author's written consent.)
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