Now in its 27th year, this Bay Area saxophone quartet is a genuine institution. The members of ROVA (the name is an acronym of the surnames of the founding members, all still present except for Andrew Voigt, replaced in 1988 by Steve Adams) are all tremendous, flexible players, and the group's voluminous discography displays their immense range, encompassing coloristic abstraction and harmony-laden rhapsody, rigorous jazz improvisation and tricky through-composed experiments. The title track of their latest recording, Resistance (Victo, 2003), is a group composition whose shifting movements are complicated by prerecorded elements (including solo passages and thick chord blasts) that any member can trigger at will, forcing the rest to adjust on the fly. Over the years ROVA has also become a valued repertory group, adapting the work of forward-looking jazz composers like Steve Lacy and Anthony Braxton and, perhaps more importantly, commissioning and premiering new works from jazz and new-music composers such as Alvin Curran, Terry Riley, and Tim Berne. Freedom in Fragments (Tzadik, 2002) contains 13 richly detailed vignettes from a 23-part suite commissioned from guitarist Fred Frith. And Resistance includes a piece written for the group by trumpeter Wadada Leo Smith; called "The M'ad-Din," it's a tapestry woven of intricate ornamental lines inspired by Koranic symbols. This is ROVA's first Chicago show since 1998. Wednesday, February 11, 7 PM, Preston Bradley Hall, Chicago Cultural Center, 78 E. Washington; 312-744-6630.