The Isthmus Vocal Ensemble is presenting an “Isthmus Christhmus” this Friday night, August 6th at 7:30 p.m., Luther Memorial Church. Tickets are $15, and $10 for students/seniors. Madison Opera has a few choristers in the IVE, which performs only once a year, so if you’re craving the choral sound this will surely be a rewarding evening of music making. The program will feature Advent and Christmas choral music (“yes, in August,” as they say) by Praetorius, Lauridsen, Paulus, Rachmaninoff, and others.