It's not technically in South Bend, but I think it counts that Goshen College's radio station (based in, you guessed it, Goshen, Indiana) comes in loud and clear here in this part of St. Joseph County. I discovered this gem of a radio station only this summer (thanks to a friend), and it's been set at #1 (in my ancient car) ever since. The Globe has been around for more than 50 years and bills itself as a radio station that "features a fresh and eclectic mix of Americana, alternative acoustic, folk, singer-songwriters and world beat music." I personally can't think of a better line-up.
Some of the shows are imported from NPR while many are DJ'ed by the volunteer student staff of Goshen College or other local DJ's. My favorite NPR import is 'World Cafe', on every day from 5-7 with recent featured artists such as Robert Plant, Ray LaMontagne, MGMT, Local Natives, and Suzanne Vega. Some of the great local shows include 'Could Lead to Dancing' on Sundays from 7-9 and the 'Folk Revival' on Mondays from 7-9.
I can't recommend this radio station enough. Listen in your car or online, but whichever you choose, you should tune in now.
Check out the website (and online player) here.
Check out a program guide here.