Vijay Iyer (piano) and Rudresh Mahanthappa (alto sax) have performed as a duo for years, but Raw Materials is their long-awaited debut on disc. The repertoire, save for the final track, “Hope,” is from a commissioned suite called “Sangha: Collaborative Fables,” with composer credits split roughly down the middle. The two cover plenty of ground but aren’t at all longwinded. Somehow their impeccable precision enhances rather than limits their improvisational freedom. Their challenging rhythmic syntax, well documented on their respective quartet discs, takes on a greater immediacy in the duo context. As Iyer solos on “Frontlash” and “Common Ground,” we hear Mahanthappa double a thorny bass line with Iyer’s left hand. More than a matter of chops, it’s a riveting musical effect.
Iyer favors the sort of dark harmonic colors heard on “Inside the Machine,” “Come Back” and “The Shape of Things.” But “Fly Higher” is a detour into warped bebop, while the darting major-key cadences of “Five Fingers Make a Fist” bring to mind Dewey Redman with Keith Jarrett. Mahanthappa’s horn is a study in tonal control and dynamic contrast, from the swift and aggressive runs of “All the Names” and “Rataplan” to the legato lyricism of “Remembrance.”