Yawn, Acid. Use your freedoms wisely. Fans like me, who came of rock & roll age in the ‘70s and ‘80s, remember when a band like Yawn would not have existed without some strictures—song length, number of tangents a tune could take and still be considered a tune. Instead the band is able to throw all caution windward and do as they please. The fine points of this winding, ultimately winning, unpredictable “single” are not hard to pin down. Maybe it’s that title—“Acid”—but I can’t hear it without thinking of it as an album side on a ‘60s blues/prog-rock LP, and wondering what the distilled 45 single version would sound like.