Stephen Crump’s Rhombal Credit: Craig Marsden

Bassist Stephan Crump has established himself as a magnificent team player. He provides muscle and bone in the limber trio led by pianist Vijay Iyer, and lets his fluency with tender melody sparkle in intimate groupings including his duo with guitarist Mary Halvorson and the Rosetta Trio, with guitarists Liberty Ellman and Jamie Fox. Crump shows off a different side of his personality with his agile quartet Rhombal, which formed as a response to the death of his brother, Patrick, from an aggressive sarcoma. The foursome’s eponymous 2016 debut album on Crump’s Papillon Sounds label is grounded by the bassist’s deeply resonant, calmly measured, woody lines that consistently carve out deep grooves. Buffeted and buoyed by the brilliant drumming of Tyshawn Sorey, the band’s loose gait sometimes erupts with spasmodic, nubby accents, but the players never surrender their propulsive focus. That foundation gives loads of space to the front line of rising trumpeter Adam O’Farrill, who knocked me out when his own quartet debuted in Chicago earlier this year, and veteran tenor saxophonist Ellery Eskelin, who like Crump has a beautifully considered improvisational voice and well-proportioned tone. The music rarely hurries: the opener “NoD for Nelson” is a relaxed salute to Oliver Nelson replete with lines indebted to his classic tune “Stolen Moments.” “Grovi” is a ballad with a draggy feel, but within it lies Sorey’s forceful, sporadic kick-drum accents. The pieces are structured to allow the horns to roam freely, ranging from loose unison patterns to simultaneous improvisation to telepathic give-and-take interactions, but the quartet cleaves to the transparent forms embedded within each elegant original, such as the off-kilter funk of “Esquina Dream” and the gorgeous crawl of “How Close Are You.” For the group’s Chicago debut, kinetic powerhouse Kassa Overall subs for Sorey.   v