Dolaďovacia trubka (f)
2nd piece of a composed drone; the outermost piece of smaller drones
Centre tuning piece of the drone.
Elschek, Oskár: Die Volksmusikinstrumente der Tschechoslowakei, 2 (Handbuch der europ. Volksmusikinstr. 1/2;2 [Slowakei]). Leipzig, 1983, p.205.