The Glass Hours is bassist Linda May Han Oh’s sixth album as a leader and third for Biophilia, the innovative label founded by her pianist (and husband) Fabian Almazan. The depth and originality of Oh’s writing is what first jumps out, as well as the sheer skill that this music demands—not a problem when your bandmates are Almazan, tenor saxophonist Mark Turner, vocalist Sara Serpa, and drummer Obed Calvaire. While Almazan employs electronics alongside piano, and Oh plays electric and upright bass (and sings), The Glass Hours is rooted predominantly in acoustic jazz, even if the harmony, orchestration, and rhythmic concept are on another plane. Oh’s upright solos are virtuoso tours de force, every time (she is Pat Metheny’s bassist of choice, after all). Serpa offers spoken-word recitation on “Antiquity” and often functions as a vocal “horn” in the ensemble, joining Turner in the execution of complex lines and arranged passages, notably on “The Imperative.” The electric bass tracks are “The Glass Hours,” “Phosphorus,” and “Hatchling,” all of which inspire tremendous playing over complex forms and stormy rhythms.