Bladder pipe with double-chanter
Bladder pipe with single chanter + drone / single reeds (type?)
Depicted in the 13th century Spanish manuscript »Cantigas de Santa María«; The second tube produces a drone.
Sachs, Curt: Real-Lexikon der Musikinstrumente: zugleich ein Polyglossar für das gesamte Instrumentengebiet [Berlin, 1913]. Hildesheim, 1964 [facsimile], p.302a.