Music Theory You Need, Especially if You Don't Read: Bonus Skills

As we have explored some essential music theory for non-reading musicians in these past few articles, you may have wondered at some point, "What does this have to do with playing by ear in a band?" We did see how a little theory makes it easier to invent new chords, and we learned how each key signature represents a family of notes and chords that naturally fit together. We also discovered that knowing how to subdivide the bar and the ability to read rhythm notation can be essential regardless of whether you're playing by ear or reading a chart. In the process of learning these basic skills, you have also acquired some new skills that you never had before. Your investment in learning some theory now puts some incredibly useful musical tools at your disposal.

Arpeggios that Fit Anywhere

While we discussed how to build chords on the guitar, the bass players in the room probably instantly saw how those chord shapes were full of great potential bass lines. It is fair to say that much of the time in pop music, we encounter bass lines built around the root notes of the chord progression. Yet many of the most interesting and beautiful bass lines are built upon arpeggios. Mastering the diatonic arpeggios in every key will lay the groundwork for you to play confidently in any key, with total freedom of note choice. Even "out notes" make more sense when seen in the greater harmonic context. A very common example of this occurs in many blues melodies, when a minor third is played as a grace note sliding into a major third, as Chuck Berry chose to do on the very beginning notes of his intro to "Johnny B. Goode." When putting your knowledge of arpeggios to work, remember that they can be the basis for an entire part, or they can present different options for passing notes between chords. Learn arpeggios for every combination of strings, from patterns running up a single string, to arpeggios that reach all the way across the neck. Once you do, walking bass lines on jazz or blues numbers will be second nature.

"It's just a two - five - one progression in G..."
 

In many professional working situations, players will communicate progressions on the fly using a lingo derived from The Nashville Number System. The chord progression is given in terms of harmonic degrees rather than by the chord names themselves. As you may recall, the chords of any key can be understood as the notes of the diatonic scale applied to the harmonic degrees. In a major key, the harmonic degrees are I7 - ii7 - iii7 - IVΔ7 - V7 - vi7 - vii7b5. Applying the pattern to G major, we get G7 - Am7 - Bm7 - CΔ7 - D7 - Em7 - F#m7b5. If the bandleader tells you, "It's just a two - five - one progression in G," you know the progression will go Am7 - D7 - G7. Notice how the bandleader will assume you know which 7ths belong where (Δ7 is shorthand for a major seventh rather than a dominant 7th), even though he doesn't mention them. You also need to know the key signature. It's a shorthand system, so pay attention. In jazz, you'll find this to be the most common progression. In blues, similar expressions are used to communicate the nuances of the blues changes on a particular song, for example, "It's a V - IV - I - V" on the turnaround, or "Go to the IV chord on the second bar."

Transpose on the Fly

While it may take some practice to become fluent in using Nashville Numbers to communicate on stage, in time you will benefit from a much simpler way to share chord changes quickly with other musicians. You will also have a very simple way to transpose songs to a different key on the fly. In our earlier example, if you know the changes in G major are D - C - G - D (V - IV - I - V), then if you want to transpose quickly to D major, you can overlay the D major scale over the harmonic degrees and apply the progression. D - Em - F#m - G - A - Bm - C#m-b5, yielding A - G - D - A in the key of D major.

What's Your Takeaway?

In the course of this series, we've studied the basic essential music theory a non-reading musician needs to navigate most situations. While our goal was to help you identify and understand the basic skills you will need, the homework is up to you. Set aside time in your practice regimen to work on theory-related skills and knowledge in each of these areas, and study them diligently. Try to focus on one area at a time until you have mastered all of them. The rewards are worth the extra effort. "Well, if I'm going to learn all this I may as well learn to read music!" you say? Hint: you're probably right.

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