In many respects, 2016's Holiday for Strings by Peter Stampfel and his latest ad hoc group, the Brooklyn & Lower Manhattan Fiddle/Mandolin Swarm, feels like a sequel to his 2015 effort with the Brooklyn & Lower Manhattan Banjo Squadron, Better Than Expected. But of course, that ignores the fact that Stampfel has been making music like this since his days with the Fugs and the Holy Modal Rounders back in the '60s, when he was a pioneer of acid folk. Stampfel is a guy who believes in simply letting the music happen, and Holiday for Strings is a purposefully sloppy but charming exercise in spontaneous inspiration, as Stampfel and his ten accompanists saw at their fiddles and pluck various guitars and mandolins. (As Stampfel explains in his liner notes, the "Swarm" part of the group's handle comes from the unique buzzy harmonics of three or more fiddles playing at once.) Stampfel brings a giddy joy to many of these performances, singing numbers like "New Johnnie Get Your Gun" and "Honky Doody" with cracked but palpable glee, and while he and his fellow musicians often boast more spirit than technical skill, their love for this music is in the air even when they make unexpected left turns. Stampfel is the star of the show, but Holiday for Strings makes it clear that he's more of a guide than a leader, though he has a great knack for picking songs -- his addled, wobbly vocals on "I Can't Stop Loving You" actually suit the tune's heartbroken spirit better than some more serious readings, and the weird beauty of "Telstar" is still thrilling despite the curiosity of the arrangement. It's said that Miles Davis once told Herbie Hancock, "There are no mistakes, just chances to improvise," and even though Stampfel and his gang are aiming for some urban hootenanny rather than an intellectual investigation of the song form, Holiday for Strings similarly revels in the creative possibilities of the occasional wrong note. This album is a powerful and engaging reminder of why Peter Stampfel is still a renegade national treasure at the age of 78.