Shortly before his performance Sunday, Phil Lesh surprised many fans by confirming a special third acoustic set at Chicagos Riviera Theater. The evening did not disappoint and, in between his regular electric sets, Lesh and his current band ran through acoustic versions of Grateful Dead classics like Ripple, Friend of the Devil and Brokedown Palace, as well as Jackie Greenes Cry Yourself Dry and Bill Monroes Big Mon. Phil Lesh and Friends will perform at Bostons The Orpheum Theater tonight and tomorrow.