In popular music, the minor pentatonic scale is one of the most useful scales of all. If you only play notes from this scale in the corresponding key, you will never sound wrong. By adding the extra "blue note," the player can act even more versatile and expressively. This sequence of notes is commonly referred to as the "blues scale" and is very popular among guitarists because it provides a wonderful foundation for solo playing. However, to play it accurately on a standard harmonica, advanced techniques need to be learned first. This is where the PentaHarp comes into play.