The high voltage version of that is called a Marx generator. The Museum of Science and Industry in Chicago used to have a million volt Marx generator made by General Electric. The parallel to series switching was mechanical. The "crack" when it fired echoed through the whole building.
I know exactly what you're talking about! I used to go there so often as a kid and definitely remember the crack. (Also nearby was that exhibit where you could perform electrolysis on some water. It had a "push to start" button that was activated by touching some glass with a button outlined by a red decal. I still don't know how that works.)
Something else stuck in my head from that museum was the Operation Lifesaver displays around the model train exhibit. I think my dad was a little freaked out by how many times I wanted to watch the video of the train hitting a car.
Honestly, I'm a little disappointed every time I visit a museum because of how much fun I had at MSI as a kid. I think a lot of that was from being a kid, but ... good museum.
They've downsized to a Tesla coil.