[ jazz/improv ]

Ars Nova Workshop picked a daring dilly with which to start its 12th season: a duo performance by wild vocalist Jen Shyu and contrabassist Mark Dresser. I've long loved the downtown NYC-based Dresser for his pliant participation on seminal avant-albums from the likes of John Zorn (Dresser is a Tzadik label all-star), Anthony Braxton and Tim Berne. As an improvisational soloist, his 2010 release Guts: Bass Explorations, Investigations, and Explorations raised his own bar and set the stage for Synastry (Pi), his effort with dancer, multi-instrumentalist and vocalist Jen Shyu. On this duo project, both artists overstep their boundaries when it comes to improv, prodding and parrying through Synastry as if they were Olympic fencing champions. Shyu, a singer renowned for 2002's solo album For Now, is no slouch when it comes to collaboration: She was an 11-year-old finalist at the Stravinsky International Piano Competition, operated as part of Steve Coleman's Five Elements and can fly vocally in several different languages including Portuguese, Mandarin, Taiwanese and Pinuyumayan. If the rest of Ars Nova's autumn season of shows is as cutting as this gig, we have one auspicious year ahead of us.

Wed., Sept. 14, 8 p.m., $10, at Philadelphia Art Alliance, 251 S. 18th St., arsnovaworkshop.org.