Watch the D7 sus 4 Tuning online guitar lesson by TrueFire from Play Acoustic Guitar 9: Advanced Style Diversity
D7 sus 4 Tuning - Overview is a video guitar lesson presented by Vicki Genfan and is sourced from Essentials: Open Tunings.
This tuning has the feeling of mischievous joy to me. The first composition that came through to me was ‘Kali Dreams' which is about my crazy kitty, Kali. Something about the dominant 7 along with the sus4 that gives the feeling of fun (dom7) and yet suspended wonder (sus4) - what's going to happen next? Listen to the piece and you'll see what I mean. And yes, for the modal thinkers - if you're in the key of D the tuning is reflecting the mixolydian mode.
It's really fun to play around with single note scale runs and riffs in first position using the open strings along with fingered notes. I've ended the etude for this tuning with an example of that. For fun: Find some chords in the key of G.