It was billed as Abigail Washburn with Casey Driessen and Ben Sollee, names of three members from the folk outfit The Sparrow Quartet, but upon entering the cozy Joe’s Pub, the presence of a fourth chair onstage stood out. As luck would have it, the esteemed Béla Fleck did turn out; due to corporate entanglements, he could not be named in conjunction with the event promotion, but cunningly proved capable of filling the seat and completed the quartet.

Each of the musicians―Washburn and Fleck on banjo, cellist Sollee and Driessen playing fiddle―are steeped in roots, folk and bluegrass music but collectively, The Sparrow Quartet breaks away from purely American genres. While Washburn sings in Mandarin as well as English, songs venture into traditional Chinese music. Most of the songs came off the groupʼs album, Abigail Washburn and The Sparrow Quartet, though a couple came from Washburn’s solo release Song of the Traveling Daughter. Every so often, Washburn ardently introduced her cohorts and noted their accomplishments before each took a turn to fly solo.

The Quartet opened with “Overture” to give the audience a taste of the catchy banjo sounds and a brief bit of yodeling from Washburn. Moving without pause from “A Fuller Wine,” they linked the Appalachian Trail to the Silk Road on “Taiyang Chulai,” which turned a frenzy of violin and Mandarin singing into a barn stomper. To further spice things up, Washburn regaled a Chinese tale of a sheepherder who falls in love with a woman washing clothes in the river ( “Kangding Qingge/Old Timey Dance Party” ). On this fine song, Fleck’s virtuoso plucking interspersed with Washburn’s sharp Mandarin punctuations, further connecting the musical traditions.

With time for just one more, Washburn added suspense to Henry Green’s curious gospel “Strange Things,” sounding like a spirit possessed her as the music picked up a frantic tempo and ominous tone.

Applause brought the group back for an encore and Fleck asked for a show of hands to decide between a slow or fast song; fast won out. The Quartet then mashed The Beatlesʼ “Eleanor Rigby” into a delightful extended bluegrass jam. Already well beyond simple toe-tapping appreciation, the crowd rejoiced at this unexpected treat and returned an even more resounding applause than before.

The late set at Joe’s Pub was a success and the members of The Sparrow Quartet parted ways after one more show in Kentucky. But each of these brilliant musicians have their own projects to focus on (e.g. Fleck’s upcoming documentary _Throw Down Your Heart+) and the foursomeʼs album is a testament to the timelessness of traditional music.