The sound of drums

I'm doing a spot of work at home this Saturday afternoon and have the window open, what with the outside temperature being a very mild 15C today. And I can hear drum beats in the distance! I assume the sound is being made by Swiss Fasnacht groups practicing down in the woody meadows along the River Wiese where the German/Swiss border runs. They tend to rehearse their repertoire down there as it's a fair distance from any built-up areas. It still makes a heck of a racket though, and can usually be heard clearly by anyone walking up Tüllinger Hill in Weil this time of the year.