Here's two grooves for you, both played over a static C bass pedal. The first groove starts with the IV chord on the note C. I play all the other quartal voicings in relation to this one using the sequence outlined in the tutorial giving me a C lydian groove.
On the second groove I play the II chord from C giving me a C dorian sound again. You can distincly hear the modal sound of each groove.
I've provided a backing track of a static C pedal for you to try this on.
Enjoy!