Chicago’s free-on-the-grass outdoor Grant Park Symphony concerts have audiences that come no matter what, open to the eclectic mix that conductor Carlos Kalmar chooses. This season is rich in premieres, in part becomes some were held over from last year’s Covid impaired schedule. The June 19 features a Chicago composer deserving of national recognition – Mischa Zupko, whose high-energy “Blue Matter,” for symphony and chorus, is receiving its world premiere two years after it was originally scheduled. And Los Angeles composer and jazz pianist Billy Childs will hear his new Violin Concerto No. 2 on July 15, performed by Rachel Barton Pine. Since 2014, the Grant Park Music Festival has committed itself to the new works, commissioning 22 to date. Here’s a list.