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Excruciatingly Basic Jazz Theory

By Rob Brethouwer

     Even if they are not understood completely, the building blocks of a topic are important to have in mind. For some, the building blocks are understood up to a point and then things become fuzzy. For others, the blocks themselves are an enigma. Theory is the building blocks of music. One other way to think of theory is to refer to it as standard notation. This notation is universal and is used throughout music regardless of the verbal language may be used to describe the music.

     For our purposes, we will start with a C major scale. If you ever took piano lessons, this may well have been the scale used to learn finger position on the keyboard. This was the white key in the middle of the piano keyboard. On a piano, the C major scale is all white keys. The notes of the scale are C-D-E-F-G-A-B and then back to C. If numbers were to be used instead of letters for this scale, it would be 1-2-3-4-5-6-7 and then back to 8. In standard notation, this scale would be noted as I-ii-iii-IV-V-vi-vii and then back to I, referred to as the tonic. For this discussion on jazz theory, one change will be made. Instead of the last note going back to I, the tonic, or 1, the first note of the scale, we will refer to the last C as 8. So, now we have 1-2-3-4-5-6-7-8. We want to continue the number sequence because it is the pathway to describing jazz chords.

     A chord is simply the notes of a scale stacked on top of each like a snowman, played at the same time if on a piano. In classical music, a piece of music may be in a certain key, say C major. The key may change throughout a piece or a movement, but this primary key is what the piece of music is written around. In a jazz chart (song, tune, piece of music), the tonal center of the piece will change often, sometimes as often as every four bars or measures. This is referred to as a chord change and this is what the musicians “play under” when they improvise. Keeping in C major, a jazz chord may be noted as C-7 #11 (#=sharp). The “7” after the C means that the seventh tone of the scale will be lowered by a half step. In C major the B is now a B-flat. Our C-7 #11 chord is broken down as C-D-E-F-G-A-B flat-C-D-E-F#, or 1-2-3-4-5-6-flat 7-8-9-10-sharp 11. As you can see when things are broken down and written out individually, the jazz musician has a good number of notes to choose from within this chord.

 Using these same building blocks, let us expand into a more complex key and look at a more complex jazz chord. A-flat major has four flats in the key signature, B, E, A, and D. Written out the notes of the scale are A-Flat, B-flat, C, D-flat, E-flat, F, G, and back to A-flat. Again, this is simply 1-2-3-4-5-6-7-8. Expanding this key into a chord used in jazz we could have A-flat, #9, #13. First, we need to look at this chord as an entire scale, A-flat, B-flat, C, D-flat, E-flat, F, G, A-flat, B-natural (our sharp 9 raises the B-flat by a half-step) C, D-flat, E-flat, F# (the #13 raised the F-natural to an F#). Second, we will look at this chord as a I chord (root or tonic position). A-flat, C, E-flat, B-natural, F#. These are the individual circles of our snowman. Finally, and this is as far as we will go, let us build on the fifth tone of the I chord in A-flat. Counting with the A-flat as I, the fifth tone is E-flat. Using the same chord structure, we can now have V#9#13 in A-flat. The snowman based on the V is E-flat/B-natural/F#. Always think in terms of these three steps and the idea will have a great place from which to expand.

     It is not important that you fully grasp these concepts. What is important is knowing some basic on how jazz works. If you ever hear a musician say, “playing under the chord”, you now have some idea what they are talking about.

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About the Author

Coming into existence on a dark winter evening, Rob Brethouwer was born to have a book in his hands and a sarcastic remark on the tip of his tongue. A first career is in its late stages and a second short career as a librarian is in the early stages of training. A former classical music columnist with 151 articles out in the world, Rob now turns his pen towards the world of jazz. Obsessed with big cities and subway systems, Rob does what he can to cope with living in small-town America.

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