Clark Sommers Credit: Christine Jeffers

There’s a reason dark, woody-toned bassist Clark Sommers is a ubiquitous presence on the Chicago jazz scene—not only does he have impeccable timing and bulldozer force but he’s incredibly versatile. That last quality is a true hallmark of great Chicago musicians of the past, who often had to adapt to all manner of gigs to earn a living, whether playing in pickup bands for a touring R&B singer or playing polkas at a Polish function. Within the jazz microcosm he’s remarkable, bringing a bruising but ebullient rush to his trio Bash with saxophonist Geof Bradfield and drummer Dana Hall, or quicksilver agility in support of sophisticated singer Kurt Elling. He shows off his more mainstream side with his new all-star band Lens, where he in typical fashion downplays his own virtuosity in favor of his ability to anchor an album with muscular, full-blooded lines—he takes only one solo on the band’s brand-new debut album, By a Thread (due from Ears & Eyes on July 21). The recording features some of his steadiest cohorts, including Bradfield, trombonist Joel Adams, and former Chicago guitarist Jeff Parker (whose mainstream chops here remind listeners just how deeply he’s rooted in jazz tradition), and Sommers also enlists some heavy hitters from New York in drummer Kendrick Scott and keyboardist Gary Versace. The tunes, all written by the bassist, glisten with a liquid finish, as Versace’s graceful work on both Hammond B-3 and Fender-Rhodes helps toe the line between sleek soul jazz and a fusion sound not far from late Steely Dan, albeit one that privileges no-holds-barred improvisation over cold perfection. For this weekend’s concerts Sommers, Parker, Bradfield, and Adams will be joined by some terrific subs, including drummer Hall and organist Stu Mindeman.   v