Despite its conventional string-band arrangement—guitar, banjo, fiddle, mandolin, upright bass—Punch Brothers turn out bluegrass music so unconventional that it barely merits the genre tag: The group favors meandering arrangements that hew closer to jazz or classical. But while its previous album, Punch, took that sophistication to a level bordering on esotericism, the new Antifogmatic is as warm and welcoming as the bracing 19th-century drink that gave it its name. Partial credit goes to producer Jon Brion, who injects some of his pop sensibility into the songs without stripping them of the flourishes that make them so compelling. “You Are,” for example, is anchored by a killer, rock-influenced chorus as it twists through five minutes of crescendos and tempo changes, allowing the band’s virtuosic playing to shine without becoming tedious. But ultimately, Punch Brothers’ sense of camaraderie and whiskey-soaked outlook—on fine display on the twangy album highlights “Don’t Need No” and “Rye Whiskey”—are what make the album so inviting. The occasional moments of extended instrumental noodling—particularly in the album’s back half—might frustrate listeners who aren’t enamored of mandolin pyrotechnics. But the showy displays of musicianship are backed up by solid songwriting and a willingness to simplify when called for, as on the gorgeously sparse album-closer “This Is The Song.”