Director Ryan Heller leads the 40-voice Chorus Austin Vocal Arts Ensemble in a concert featuring works by Austin, Texas, and southwestern composers: Donald Grantham, Craig Hella Johnson, Abby Gostein, Thomas Pavlechko, Robert H. Young, Stephanie K. Andrews, and Benjamin May. May 17-18. Sat., 8pm; St. Theresa Catholic Church, 4311 Small. Sun., 3pm; St. Martin’s Evangelical Lutheran Church, 606 W. 15th. $20 ($15, seniors, students).