Arlington Tx Guitar Teacher John E. Davis covers all five pentatonic and corresponding diatonic scales during this rock and metal guitar video lesson. Davis shows how to play three open string metal guitar licks in the key of E Minor. Beginner Guitar Lessons. Tremolo Picking, Finger Tapping and Legato licks are covered. Rock Guitar Lessons. For more information visit www.TexasRockGuitarist.com.