If you are one of those people, you missed out on a great, great combo of bands on Austin City Limits. The Avett Brothers are difficult to pigeonhole, insanely talented who filter things through a bluegrass lens, but are not just about the country singing. Try to get past the fact that they kind of look like a band made up of Ashton Kutcher and Demetri Martin, and enjoy the fact that they right direct, honest songs about love and loss, and aren't afraid to rock it a little.
Heartless Bastards are a more straight-forward rock band, but with a potent weapon in lead singer and guitarist Erika Wennerstrom--she's got a voice you simply haven't heard before, and her guitar ain't for show. If you can watch 25 minutes of her go and not end up crushing on her at least a little, you are a better person than I. Or you are just dead inside.
The entire episode is right here on the PBS website.