The Chicago Philharmonic season kicks off with a celebration of Love’s great couples: Romeo & Juliet, Tony & Maria, Daphnis & Chloé, Tristan & Isolde, and Ruslan & Ludmila. The orchestra performs colorful music of blissful excitement, heart-wrenching longing, and everything in between as soprano Emily Birsan and tenor John Irvin, both recently engaged by the Lyric Opera, bring their knock-out voices to this afternoon of orchestral works and love duets.