Watch the Adding the 9th and 13th online guitar lesson by Fareed Haque from Jazz Rock Workshop
Proceed with this tip at your own risk! By adding the 9th and 13th to the pentatonic scale, we have turned the 5-note pentatonic scale (penta in Greek means 5) in to a 7-note scale.
This is sometimes called a Major scale. But don't tell anyone. It'll be our little secret.