Thoroughly steeped in a variety of global musical styles, the pan-ethnic Antwerp collective Think of One has been puzzling pundits in Europe and beyond for the past five years. Their propensity for recording and performing under different names, their prodigious and varied output (this is their eighth album in five years) and their unwillingness to conform to expectations makes them perhaps the most punk-rock world music outfit currently working. Forsaking purity for a party, Tráfico is theoretically rooted in Brazilian forms (the album was written in Recife), but from that basis, the group bounces from gypsy thrash to giddy balladry, from free-form freakouts to gently rocking jazz. Somehow, the group channels the spirit of tropicalia’s boundless experimentation and pick-and-choose sonic approach but doesn’t wind up sounding like so many of the third-rate Os Mutantes tribute acts out there. Ultimately, they sound neither Belgian nor Brazilian; they sound like the band that will save “world music” from itself.