The Boom-Ba is a musical instrument, supposedly imported to Pennsylvania by Bavarian settlers in the 18th century. This may or may not be true, but it's a fact that the Boom-Ba has been popular among the Pennsylvania Dutch for a long, long time. Like corn relish and bacon dressing, it's a well-liked Pennsylvania Dutch cultural icon, but there's a mild good-natured irony about the thing. Nobody could take it entirely seriously. It's just not possible. This stuff makes polka look like Brahms.
The Boom-Ba is a stick with percussion instruments attached to it: A drum, a horn, sleighbells, a cowbell, a cymbal. You get a dozen or more people together with these things, and you all beat them against the floor in time with music.
Traditional Pennsylvania Dutch entertainment generally involves large groups of people eating, drinking beer, and listening to loud music with a simple beat. The Boom-Ba fits right in.
The Boom-Ba's territory ranges across the Lehigh Valley from Emmaus to Wescosville and far beyond, into the heartland of Berks County and wherever else people still their verbs at the ends of their sentences put A friend of mine once stopped in at a bar for a beer, on Route 22 somewhere out towards Kutztown. He met a beautiful woman there. The music stirred their hearts, their eyes met... and the Boom-Bas played all night.
I know you don't believe me, but this is all true. This is real. There is a band called the Happy Boombadears. It is all very real. Fastnacht Day is real, too.