Though Vijay Iyer and Rudresh Mahanthappa are floating on a decade-long history of collaboration, their self-titled Raw Materials release is the first recorded project the relationship has generated. The bulk of this disc is dedicated the suite Sangha: Collaborative Fables, and though they ping-pong the writing credits back and forth, these are clearly two musical minds in sync. “Remembrance,” as the title implies, marks one of the more introspective portions of the work. Iyer’s running piano lines ferry the listener though from start to finish, with Mahanthappa’s alto sax stepping in to highlight portions of the score with more brilliant colors and textures. Neither man seems inclined to show off for the microphone; rather, the sparks come from the exponential level of energy they rise to create in the space in between them.