The King is Naked, folks... this humble tubes - i.e. a non-directly heated double triode - made in Ulm, West Germany in 1965 has its own soul!
I used for years WE421A tubes in my DIY little amp... then, one day, I discovered substitutes... GEC A1834, first, then this German-made tube.
Up to date, the 6080 has a clarity, a natural introspection and a seldom experienced dynamic palette so well discerning from ppp to FFF and all nuances in between... well: Telefunken is the winner... in the next days I’ll extensively try and listen to GEC’s...
BTW - my reference disc these days is Valentine by Bill Frisell Trio on Blue Note label... Bill’s guitar(s) and effects and double-bass and drums are so rich and the recording is first rate!