How did the Modzitz Ein Kitzva sweep the globe and become the de facto tune used by everyone in the world for the conclusion of Unetana Tokef? OK, if I am being honest I've not spent the YN in more than seven places. Hardly the whole world. Yet the Modzitz is used in all seven places.
When I was a kid, our parents used other tunes. I don't remember any of them. But I remember when the old men who ran our place hired a guest YN chazen who came with the Modvitz tune. It was hugely popular. A big hit right from the beginning. Even after the guest YN chazan got cashiered we forced his replacement to use it. On new guy's first day, he tried to start another tune, and the gabbai actually went over and straightened him out, humming the Modvitz and bouncing his hand up and down in time with the melody.
When I got married, the tune was alredy waiting for me in my father-in-law's shteeble and in the agudah he switched to a few years later. Later, when I moved to my own neighborhood, the Modzitz tune preceded me, and it beat me to my next destination as well. How does a tune take over the world? The why part is easy -- its catchy and fun, but how does it spread from one congregation to another, when people generally daven in the same shul, with the same chazan year after year. Ask the same question about the Kol Nidrei or Neilah nusach, too, I guess. What are the mechanics of their conquests?
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