(Note from Tony) - my students have to do lessons each semester and submit them on the site. Sangwon speaks much better Korean than English so he's doing his lesson in Korean.
I recently acquired a marimba, and started messing around with some stuff!
One side of technique seems to be about faster harder and louder. On most gigs I do there's at least one tunes per set, usually that require fast loud and hard. People talk about these tempos and volumes as being unmusical, but I don't think they are. Especially when incorporated in a set of music, they seem to fit well. It's when the whole set becomes fast loud and hard that things get to be a drag. If my wife is in the audience, when I get through the set she usually says to me, that was a lot of testosterone being thrown around that stage.
Here's an exercise I used to do. Play it fast, hard and loud. That's the key. Sounds a little like a Steve Reich piece. Build up speed, play each pattern longer, etc. etc. etc. Stamina.
I just worked on this with a student. I wrote out some two five one progressions where the chords keep moving down.
Where chops come in is this: You practice this and work up speed. Play 2 5 1 6's in different keys. This would really help your chops!
I've attached the 'rough' pdf I made for the student.
Here are all Behn's lessons on lines. Check out they are great. a