Many popular rock and blues songs use a basic pattern to create fast pentatonic scale runs. One of the more famous uses of this technique is Eric Johnson. It involves playing 4 ascending notes, then jumping down three, and playing four more sequentially ascending notes. So, it basically looks like
1 2 3 4 2 3 4 5 3 4 5 6 4 5 6 7
and so on.
The way most people play this is using the same shape they used to learn the pentatonic scale: the basic minor "box" shape. This is an easy shape to memorize and can be played without moving the position of one's hand up or down the neck. There's no reason not to use this shape if you're playing a slower melody, but to create the rapid flurry of notes that is popular in rock, metal, and jazz music, it may be preferable to play the notes while moving up the neck. There are a few benefits to this, which we'll look at later.
First, let's look at the tab for how people usually play this. We'll be in the key of G minor for the whole lesson, by the way:
|----------------------------------------------------------------3---|
|------------------------------------------------3-----3-6---3-6-----|
|--------------------------------3-----3-5---3-5---3-5-----5---------|
|----------------3-----3-5---3-5---3-5-----5-------------------------|
|------3-5---3-5---3-5-----5-----------------------------------------|
|--3-6-----6---------------------------------------------------------|
Playing this little peice, you can probably already hear how it is incorporated into many guitar solos. However, you'll notice that there is a lot of switching strings involved, and you are also limited to playing two octaves using this shape. The way that we're going to look at playing will definitely feel a little awkward at first, but with practice you will find that it'll be much easier to play.
What we're going to do here is start by playing two notes on the sixth string, and then two notes on the fifth string. Then, we're going to play one note on the sixth string, and _three_ notes on the fifth string. Then, continue the pattern while smoothly shifting your hand up the neck. It's easier to see by playing.
|------------------------------------------------------------------------|
|------------------------------------------------------------------------|
|-----------------------------------------------5-7------7-10----7-10-12-|
|----------------------3-5-----5-8---5-8-10-5-8-----8-10------10---------|
|------3-5---3-5-8-3-5-----5-8-----8-------------------------------------|
|--3-6-----6-------------------------------------------------------------|
Now, as you can see, we've gone up two octaves from G to G, just like in example 1. However, we can continue to play this pattern all the way up to the high G on the fifteenth fret, and even higher if you wish.
As I've said already, this is a difficult pattern to get under your fingers, but when you do you'll find that its well worth it. Its more versatile, easier to play quickly, and sounds more fluid at higher tempos.
Once you feel confident in the basic pattern, try transposing it to other keys, such as A, D, or E minor. Also, work on learning it backwards, starting from the high E string and working your way back along the fretboard.
Good luck!
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