Although it’s quite tempting to add the minor 3rd that is so significant in many blues licks, we have to control our natural impulse in order to get the exotic feel. In a way, this is the essence of playing this type of music, which demands control from us and allows us to meditate on one scale in one frame of mind.
As you might know, the minor blues scale has that unique note that distinguishes it from the pentatonic scale (the augmented 4th or diminished 5th). In Am blues, for example, it’s Eb or D# (They are enharmonic tones, same pitch, different names). But when should we call it the first or the latter — and what’s the difference?