Have subsequently done some more reading, and the singer evidently later formed the band Survivor in the 80s - and got a few hits with them. Also he wrote some hit songs for some other artists too (and some jingles for advertising). And, at least as of a few years ago, has been touring. There is something about that wall of sound of a band with guitar, drums (percussion), bass, keyboard, and a well integrated horn section. Live it WILL send shivers up your spine like you say. Last time I heard Chicago was maybe over 10 years ago now, but they still sounded great.
I never heard the Big Band sound of Brian Setzer live but that would be another animal all together, but killer in its own right. My mother loved that before she passed away. She was once quite a "jitterbugger" (or so I have heard).
