The place to go in the 60's in Chicago was the Kinetic Playground, aka Electric Theater when it first opened, on Clark St.
It had a large round open area with the stage and the walls around it were used for various projected psychedelic images. You'd sit or stand on the floor and they had dudes with the white fung-fu pajamas walking around so no one got out of hand. It also had a juice bar, no liquor, and some munchies were sold there.
My group of friends would be there most weekends as we didn't live but a couple of miles away. Saw a lot of the famous groups there, Iron Butterfly included, and some not so famous nation wide. I remember one New Years Eve we saw the Byrds, Fleetwood Mac, and Muddy Waters. I particularly remember the Byrds stunk as a live group, lol.
They had a local group, Rotary Connection, play there quite often. We used to see and talk with Minnie Riperton at the juice bar. Man what a sweet voice she had.
Fun days.