Independently, German saxophonist Philipp Gerschlauer and New York guitarist David Fiuczynski have explored microtonality, the musical practice that plumbs the infinitude of tones between C and C sharp. On this bracing new collaboration, their mastery of many untraditional tunings finds wide, uncanny expression. Gerschlauer's artful reconsideration of Coltrane's "Giant Steps" in the opener "MikroSteps" sets a hall-of-mirrors tone for the recording, with Fiuczynski letting fly ringing bursts of altered pitches like the lovechild of Bern Nix and U. Srinivas. It's one tangled web of just-intonation Gerschlauer and keyboardist Giorgi Mikadze weave on Fiuczynski's "Walking Not Flying," matched by fretless bassist Matt Garrison's seismic glissandi and, elsewhere, his superb solo on "Last Chance." The not-so-secret weapon is legendary Woodstock-based drummer (and past employer of Fiuczynski and Garrison) Jack DeJohnette, imbuing this singular project with his own distinctive delicacy, iridescence, and jouncing wallop. Rarenoiserecords.com.