In the past three years, the members of English folk band Mumford & Sons have morphed from bluegrass strummers into stadium-filling superstars, all with only one full album under their belts. After a world tour, six Grammy nominations, and a performance alongside Bruce Springsteen, the group is ready for more. The band recently debuted “I Will Wait,” the first track from next month’s Babel. As the follow-up to 2009’s massive Sigh No More, Babel has a lot to live up to. Fans of the band’s jangling banjo, warbling vocals and sentimental lyrics won’t be disappointed by the new track — the group doesn’t stray too far from the formula that made it famous. “I Will Wait” is a swirling bluegrass ballad that highlights Mumford & Sons’ strengths, while managing to show a more optimistic side of the band. Babel is due out September 24 via Glassnote.

STREAM: Mumford & Sons – “I Will Wait”