Watch the Augmented Dorian online guitar lesson by Brad Carlton from Chord Studies: Modal Progressions Vol. 1
Here is another Quartal harmony chord vamp. The first chord which occurs on the 2nd, 3rd and 4th strings, has an augmented 4th interval and then a perfect 4th interval on top of that. The second chord has two perfect 4th intervals stacked. This gives us an Am6/9 and an Am7/11.