Mumford and Sons were booked for the NPR Tiny Desk thirteen years ago, during the ‘Babel’ tour, and had to cancel at the last minute. The building they were supposed to play in has since been demolished. The band finally made it, and the wait was justified. Four songs, a string quartet, Matt Menefee on banjo, and Marcus Mumford’s voice in a room that size, backed by Ben Lovett’s harmonies on piano and Ted Dwane on bass, adds up to something that scales the band’s sound down without diminishing it. The set draws from their sixth album ‘Prizefighter’ and reaches back to 2009 debut ‘Sigh No More’ for “White Blank Page.” They closed with “Badlands,” a ‘Prizefighter’ cut they’d never played live for anyone before, followed by first single “Rubber Band Man.” Thirteen years is a long time. This made the case that some things are worth scheduling twice.