Jazz “neocons”—those who maintain that if it isn’t blues-based, it isn’t jazz—will surely reject Gently Disturbed. There’s not a 12-bar or a blue note to be found in the music of Israeli bassist-composer Avishai Cohen and his trio (pianist Shai Maestro and drummer Mark Guiliana). But the disc is too subversive, and too damn good, to bother with such rigid constraints. For starters, it turns the established piano-trio formula inside out. Bass and drums usually support the keys; bolder lineups place all three on equal footing. Cohen, however, puts his bass in command. Even when sharing head arrangements with Maestro, the bass typically has the more challenging part. On “The Ever Evolving Etude,” Cohen and Maestro reverse standard roles, the former wielding melody and solo while the latter accents him. Indeed, most major solos are Cohen’s, exhibiting fleet-fingered, blank-verse rambles through the instrument’s high and middle ranges. He has an ear for astonishing melodic complexity; the traditional “Puncha Puncha” contains one memorable example, in which the bassist virtually writes his own Jewish folk song. (Maestro does get to showcase his tender, wonderfully fractured sound, especially on “Chutzpan.”) Cohen’s compositions, which make up the majority of the album, are as nimble as his arrangements and playing, and every bit as unconventional: If there’s no blues on Gently Disturbed, there’s no other familiar form, either. “Seattle,” for instance, is a lovely, longing 52-bar waltz that dissolves into a free-form bass solo before the second chorus ends. Cohen also employs oblong and shifting meters (“Pinzin Kinzin” is 9/4, “Structure in Emotion” veers from 6/8 to 8/8 to 12/8), which he and Maestro overlay with odd syncopations that confound attempts to find a basic pulse. Guiliana’s simple ability to keep up, let alone stamp them with his distinctive little snare-drum smashes, proves his dexterity. The real effect of these technical subversions is to keep the music unpredictable, which also makes it deeply compelling. The unique compositional structures emphasize the tautness of the pieces—further thrown into relief by the formal waltzes of the album’s two traditional tunes—and the bass’s prominence and starkness packs a punch that lingers from one track into the next. For the neocons, that leaves only a lack of blue notes to grouse about. But if an album’s biggest problem is that it chooses one perfectly viable harmonic language over another, you’re dealing with a fine piece of music.