Expanding your acquaintance with chromaticism, polyrhythms, and counterpoint, for example, can take your playing to another level. But in this article, I am going to make a case for instead taking something you are already very familiar with and adding some restrictions to simplify it even further. This is a technique that I refer to as tetrachord soloing.
For the tetrachord soloing technique, simply take whatever scale you are playing and limit yourself to just four of the unique pitches in the scale. In the same way that a major pentatonic scale eliminates 2 notes from the full major scale (the 4th and the 7th), creating a tetrachord within a major scale eliminates 3 notes (any of your choosing).
When you limit yourself to only 4 notes for X number of bars in a solo, it creates a very strong harmonic focus for those phrases. Then, when you eventually reach outside of that limited set of notes, the newly incorporated notes that you have been purposefully avoiding have a greater significance and impact. Imagine playing a solo where landing on the 3rd or 5th sounds like an interesting note choice.
Let's look at the following 4-note grouping and discover its many applications:
1, 2, 5, b7
We'll begin by using the A natural minor scale. In this scale, the root is A, the 2nd is B, the 5th is E, and the flat 7th is G. Here are a couple of positions to play these notes on the fretboard:
Take some time to play around with these notes and begin hearing their unique sonority.
As you may have realized already, the four note grouping of 1, 2, 5, and b7 is not exclusive to the natural minor scale. This same intervalic relationship can be applied to the dorian mode and mixolydian mode, as well as several more exotic scales including the mixolydian b6 scale and the Ukranian minor scale.
Another way to get more mileage out of this tetrachord is to transpose it within the scale, rather than applying it to other scales. If we stay in A natural minor and move each note down a full step (A to G, B to A, E to D, and G to F), our new tetrachord also consists of notes found in the full scale (b7, 1, 4, b6). Another option is to transpose the original notes up by a perfect 4th (A to D, B to E, E to A, and G to C), giving us a third tetrachord within the scale with the same intervalic relationship (4, 5, 1, b3).
Note: The intervals at which you transpose a tetrachord to remain diatonic to your scale varies for each tetrachord you use. For example, and 1, 2, b3, 4 tetrachord cannot be moved up a whole step and remain in key like the previous 1, 2, 5, b7 tetrachord.
There are numerous tetrachords to try out, and I encourage you to do some experimenting. Find some sounds that you like. Find ways to connect modulating chord changes using a tetrachord. There's a lot to be gained by taking something you already know, simplifying it, and finding new, exciting applications for it.
About the author:
Charlie Button is a musician, producer, and educator from Upstate NY. His name has appeared in such music publications as Pitchfork, MySpace Artist of the Day, Dead End Hip Hop, All About Jazz, and more. Visit Charlie's website for private and group Skype guitar lessons, as well as to sign up for his newsletter that contains free video lessons and articles such as this one.