Watch the Pedal Point Comping online guitar lesson by Tom Wolfe from 50 Hard Bop Blues Licks You MUST Know
The root of the blues is a versatile tone in the blues - it can basically be played over the entire chorus of blues and fit. Even if it isn't an actual tone of the chord. This lick is directly from the style of Wes Montgomery. The root of the blues is played with chords hit on the up beat in the middle of the measures. The repetitive note is known as a pedal point - a melodic point of reference that the chords support. This phrase can build with intensity as you add other chords on different beats while maintaining the pedal point of the root.