Ravinia Festival has announced its off-season Rising Stars series for 2011/12, featuring six concerts by classical performers at the brink of international success. The series has been moved from Friday to Saturday evenings this year, and all concerts begin at 8 p.m. in Ravinia’s most intimate performance space, the 450-seat Bennett Gordon Hall. The schedule features pianist Gilles Vonsattel on Oct. 1; violinist Bella Hristova on Oct. 15; the Linden String Quartet on Nov. 5; pianist Daria Rabotkina on Nov. 19; Musicians from Ravinia’s Steans Music Institute on April 7; and vocal ensemble Calmus on April 28. Tickets are only $20, but you can save 20 percent when you buy four or more. You can also save by purchasing already discounted dinner packages. For $50, you get the performance and a 3-course pre-concert dinner at the Freehling Room in the same building as the concert hall.