• The Celestial Septet: ROVA + Nels Cline Singers

Tomorrow night at International House Philadelphia, superb jazz and improvised-music presenter Ars Nova Workshop hosts the first concert of a short tour by the Celestial Septet—a collaboration between ROVA, a San Francisco group that helped put the saxophone quartet on the jazz map in the late 70s, and the Nels Cline Singers, a muscular, flexible trio led by the guy known around these parts as the lead guitarist in Wilco.