Buddhist noise trucks

I’m just curious, are they actually playing any sort of tune? Or do they just bang drums randomly and blare whatever notes come out of their horns? The local temple organization has been at it all morning, driving up and down the road and dispelling evil spirits or whatever it is that they do.

Just to be clear, I enjoy it, as long as I’m not trying to sleep. It reminds me that I’m not in New York.