The Avett Brothers show a lot of energy and passion with the stage performance. The show I saw was not on the Watson Stage but I believe the Austin Stage. The sounds is like punk rock played on bluegrass instruments. A very "striped-down" sound, with harsh vocals at times, not bad vocals, just purposely sung off key.
The songs express spiteful feelings of lost love, bad love, or no love at all. Unlike punk rock I don’t recall any songs about rebelling against society or some other institution, but I could have just have missed it.
This was a wild show with a lot of energy. Don’t expect this to be your “grand pappy’s” bluegrass, heck not even your father’s bluegrass sounded like this.