Call it Don Carlos in French and sing it in five acts, or call it Don Carlo in Italian and sing it in four acts. Whichever, it’s Verdi’s glorious 1867 opera of a father/son love rivalry in Renaissance Spain, only rarely performed because it requires six stellar voices, one in each of the principal vocal ranges. You have an opportunity to hear Don Carlo (in Italian with English supertitles) June 19 at 4PM, as staged by da Corneto Opera, Chicago’s Concert Opera Company, with principals, chorus and 45-piece orchestra conducted by Giampaolo Bracali. Church of St. Hilary (free parking/air-conditioned), California and Bryn Mawr avenues; (847) 662-2694; $30 (a bargain).