Albert Collins used an open guitar tuning, which was an F minor triad(F C F A flat C F). He used a cappo to change keys. Advantages of this tuning are greater availability to octaves, and some bad-ass pull-offs.
His elusive cool sound was achieved by playing a Fender Telecaster through a Fender Twin with the treble all the way up, the bass all the way down, and a healthy portion of reverb.
The Iceman played in an open tuning using his thumb, index, and middle fingers in place of a pick. He played most of his licks on the top three strings and incorporated finger popping and 32nd note pull-offs to achieve an ear-scorching sound. He enjoyed comping behind other guitarists and his horn section, but when he played lead he played loud and intense. He played mostly a blues based scale, but added a second, third, and sixth note from the mixolydian mode.
