The three sisters of harmonizing Oregon band Joseph got their start playing small shows with no backing arrangements apart from Natalie Closner’s sparse guitar, a keyboard and a kick drum.

These days, they perform in front of hundreds of screaming fans at a time, with a full band in support, which turns their rich folk sound into pop and rock not unlike Edward Sharpe and the Magnetic Zeros or Fleetwood Mac. If Friday night’s packed show at Slim’s was any indication, Joseph won’t get many more chances to perform those small, solo shows again. Over the past few weeks, they have performed to millions through national TV: Conan O’Brien, Jimmy Fallon, and a handful of others.

“It seemed like only two shows ago we were playing to 30 people,” Natalie Closner said about midway through the approximately hourlong set.

Natalie and her sisters, twins Meegan and Allison, performed the same songs that they played on national television to loud applause: “SOS (Overboard),” “White Flag,” “Canyon,” and “Honest.” But what was truly telling was there were fans in the room who sang along to every other song from both of Joseph’s albums, 2014’s Native Dreamer Kin and the recently released I’m Alone, No You’re Not.

A two-song encore started with a singalong of “Eyes to the Sky,” which included openers Duncan Fellows, who were playing their final show of the tour. The multi-part harmonies and Meegan Closner’s intimate vocals — “despair that’s been sinking me” — were backed without instrumentation besides Natalie Closner’s guitar, showing Joseph’s roots as a vocal trio. The final song was “Sweet Dreams,” also the new album’s closing track, an enchanted waltz.

Duncan Fellows, an Austin band and not shaggy-haired man named Duncan with an acoustic guitar, swayed from dance pop on some songs, to post-rock on a few others and even to Kings of Leon-flavored Southern rock on tunes like “Fresh Squeezed,” where singer Colin Harman’s drawl closely mirrored that of Caleb Followill’s.

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