Watch the Beat Four online guitar lesson by Brad Carlton from Chord Studies: Evolving Blues Vol. 2
This is a slow blues triplet feel in the key of B♭. Notice how when we move from our B♭6/7 to the Fm7/11 our second and third strings move up a half step, creating voice leading. Our third chord E♭9 is played for three beats, and then we move on to the D♭13 for beat four. Listen to how we have our B♭ note on top throughout.