In popular music, blues keyboard riffs are universal. From Billy Preston jamming with the Rolling Stones to Ray Charles kicking into “What I’d Say,” blues progressions and scales serve as the basis for legendary songs and amazing keyboard solos. One of the greatest aspects of blues keyboard riffs is the musical theory behind them, which is simple enough for beginners, yet still challenges virtuosos.

An important musical tool to understand when playing blues keyboard riffs is the pentatonic scale. The minor pentatonic scale is the basis for most blues solos. Its cousin, the blues scale, adds a flatted fifth in between the fourth and fifth of the minor pentatonic. The major pentatonic is also used in blues keyboard riffs.

If you’re not familiar with these scales, here are some examples. We’ll use the key of E. The minor pentatonic consists of the tones 1, b3, 4, 5 and 7. So in the key of E we would have E, G, A, B and D. To change this to the blues scale, add the flatted fifth, which is bB. This gives you the notes E, G, A, Bb, B and D. The major pentatonic consists of the 1, 2, 3, 5 and 6. In the key of E, this gives us E, F#, G#, B and C#. By learning these scales up and down the keyboard, you will have a base on which to build some awesome blues keyboard riffs.

So how do you make these scales mourn and wail like only the blues can? By knowing them inside and out, you can make musical theory sing. Running up and down scales will just make your blues keyboard riffs sound like finger exercises, but knowing how to blend major and minor pentatonic together will leave your listeners astounded. The key is to understand how blues keyboard riffs incorporate each scale over different chords.

For a basic twelve-bar blues progression, the choice of scale is open, with a few basic rules thrown in for good measure. One of the basic rules to keep in mind is that there are two easy scales to use over any one chord. If you’re playing over an E or E7 chord, you can choose to use the E minor pentatonic or the E major pentatonic. By alternating between the notes of these two scales, you’ll find a variety of notes from which to choose when playing blues keyboard riffs.

You can change any of the minor pentatonic to the blues scale for some added flavor. To do this in the major pentatonic, it may be easier to visualize the scale differently. Take the root of the chord and drop it a minor third. For example, if A is the root, then you would go down to F#. Now play a minor pentatonic in this key. You’re using the same notes as the A major pentatonic, just starting on a different root. Change it to a blues scale and you’ll have the notes F#, A, B, C, C# and E. Now you’ve got another blues scale to play over an A chord! It’s that simple, and it works for any key.

By mastering the use of these scales, you can play any blues keyboard riffs that come your way. The trick is to practice them until you no longer have to think about the notes; you just feel them under your fingertips. Then you’ll wail and mourn like only the greatest blues players can.