The String Cheese Incident, a group of five musicians from Colorado, has proven the old adage true: the band that jams together, stays together. Founded in 1993 as a group of six, the band has managed to lose only one of its members over a decade and a half of busing and playing together. And the group will be coming together again, as all six members are featured on its newest album, “Trick or Treat [Live].”

The group’s new effort is a 9-disc recording of what they call “epic SCI ‘Hulaween’ shows” (sic). Staying true to SCI’s bluegrass, rock and funk roots, the album displays the kind of extended performance that one would find at any of its Birkenstock-riddled concerts, all laced with the background sounds of a cooing audience. 10-minute tracks develop over long bars and structural progressions that, to ears unfamiliar with the band, are sure to cause severe headaches. The guitars and bass echo and boom in a way that is incongruous, but eventually mesh with the electric mandolin and drums to weave musical harmony from disjointed strands of chaos. It can be overpowering, but for those initiated into SCI’s barefoot jam headspace, the String Cheese Incident could have handed out no sweeter ear candy than “Trick or Treat [Live].”