It’s a little after five on a fall Sunday afternoon. On the patio outside the Ann Arbor Distilling Company, multi-instrumentalist Brennan Andes is tuning his stand-up bass, while drummer Jon Taylor sets up his kit. A young couple near the makeshift stage area are sipping drinks and speaking Italian. Andes overhears, says, “scusi,” and walks over with his four-string banjo. Mixing Italian and English he offers to later play “Pizzica,” an Italian folk dance tune, and strums a few bars.

The exchange signals both the content and tone of the evening to come: unexpected, unplanned music, and a friendly, casual atmosphere.

Andes, who’s long played in several bands, perhaps most prominently with the Macpodz, has been fronting Andes and Friends, a constantly changing collective of musicians, Sunday nights at the A2DC since October 2017. “You never know who’ll come down,” he says. “Last week we had Dick Siegel and Madcat [Ruth]. The only criteria is you have to be a friend.”

This evening Andes and Taylor start with up tempo bebop tunes. The instrumentation is spare and atypical, but it works well; both musicians are adept on their instruments and comfortable in the idiom. The small crowd applauds each solo and tune. Andes switches to banjo for a few original pieces, including his Latin-inflected “Water Hill Liberation March.”

Brant Losinski stops by with his guitar and joins in. The music changes to traditional Irish tunes and Losinski’s aptly titled “Sweet Whiskey Dream.” For the next set, guitarist Dylan Charles–like Andes, a Community High School graduate and an alum of Vincent York’s jazz program–sits in, literally on his guitar case. The trio impressively plays Wes Montgomery’s “4 on 6,” then the promised “Pizzica,” which starts slowly, accelerating with each repeat.

For the third set, A & F regular, trumpeter and Macpodz member Ross Huff arrives, and bassist Josef Deas, another CHS and Vincent York grad, stops by on his way to his regular Sunday gig at the Ravens Club. The quartet plays an extended blues, with everyone soloing in turn. The crowd has swelled, as has the applause.

Two Sundays later, the weather has turned cold, and A & F are inside the A2DC, tucked into the corner next to the bar. The roster and instrumentation is somewhat different, but the variety and easy informality is identical. Andes, sans bass, has his banjo and acoustic guitar and is sitting before a Chinese harp-like instrument, the ancient guzheng. Huff and Wire in the Wood violinist and A& F regular Jordan Adema complete this week’s lineup, and the trio expertly glides through an eclectic repertoire, from country to swing to meditative originals featuring the guzheng. Bartender Mark Gleason occasionally provides inadvertent but accurate percussion using a bar shaker like maracas and even sings the slow blues number “Red House,” all the while continuing to wash dishes, mix drinks, and ring up sales.

The tip jar sits on the end of the bar; it has replaced the previous week’s open banjo case, and the patrons drop money, occasionally eliciting cheers from the musicians. The evening concludes with the beloved “Besame Mucho,” played as smoothly and deliciously as the White Russian Gleason made for me earlier.

Brennan Andes & Friends plays at Ann Arbor Distilling Co. every Sunday in December.